1322640 has 120 divisors (see below), whose sum is σ = 4874688. Its totient is φ = 318720.

The previous prime is 1322621. The next prime is 1322641. The reversal of 1322640 is 462231.

1322640 = T₄₀ + T₄₁ + ... + T₁₉₉.

It is a happy number.

1322640 is a `hidden beast` number, since 1 + 3 + 22 + 640 = 666.

It is a tau number, because it is divible by the number of its divisors (120).

It is a Harshad number since it is a multiple of its sum of digits (18).

It is not an unprimeable number, because it can be changed into a prime (1322641) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 7837 + ... + 8003.

2^1322640 is an apocalyptic number.

1322640 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 1322640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2437344).

1322640 is an abundant number, since it is smaller than the sum of its proper divisors (3552048).

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

1322640 is a wasteful number, since it uses less digits than its factorization.

1322640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 197 (or 188 counting only the distinct ones).

The product of its (nonzero) digits is 288, while the sum is 18.

The square root of 1322640 is about 1150.0608679544. The cubic root of 1322640 is about 109.7692131029.

Adding to 1322640 its reverse (462231), we get a palindrome (1784871).

It can be divided in two parts, 132 and 2640, that added together give a palindrome (2772).

The spelling of 1322640 in words is "one million, three hundred twenty-two thousand, six hundred forty".