1622720 has 56 divisors (see below), whose sum is σ = 4224528. Its totient is φ = 588800.

The previous prime is 1622711. The next prime is 1622729. The reversal of 1622720 is 272261.

It is an interprime number because it is at equal distance from previous prime (1622711) and next prime (1622729).

It is a hoax number, since the sum of its digits (20) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (20).

It is a junction number, because it is equal to n+sod(n) for n = 1622692 and 1622701.

It is not an unprimeable number, because it can be changed into a prime (1622729) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3290 + ... + 3750.

It is an arithmetic number, because the mean of its divisors is an integer number (75438).

2^1622720 is an apocalyptic number.

1622720 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1622720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2112264).

1622720 is an abundant number, since it is smaller than the sum of its proper divisors (2601808).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1622720 is a wasteful number, since it uses less digits than its factorization.

1622720 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 489 (or 479 counting only the distinct ones).

The product of its (nonzero) digits is 336, while the sum is 20.

The square root of 1622720 is about 1273.8602749124. The cubic root of 1622720 is about 117.5117235926.

Adding to 1622720 its reverse (272261), we get a palindrome (1894981).

It can be divided in two parts, 162 and 2720, that added together give a palindrome (2882).

The spelling of 1622720 in words is "one million, six hundred twenty-two thousand, seven hundred twenty".