621722 has 4 divisors (see below), whose sum is σ = 932586. Its totient is φ = 310860.

The previous prime is 621721. The next prime is 621739. The reversal of 621722 is 227126.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 491401 + 130321 = 701^2 + 361^2 .

It is a nialpdrome in base 15.

It is a junction number, because it is equal to n+sod(n) for n = 621694 and 621703.

It is not an unprimeable number, because it can be changed into a prime (621721) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 155429 + ... + 155432.

2⁶²¹⁷²² is an apocalyptic number.

621722 is a deficient number, since it is larger than the sum of its proper divisors (310864).

621722 is a wasteful number, since it uses less digits than its factorization.

621722 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 310863.

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

The square root of 621722 is about 788.4935002903. The cubic root of 621722 is about 85.3490605507.

Adding to 621722 its reverse (227126), we get a palindrome (848848).

The spelling of 621722 in words is "six hundred twenty-one thousand, seven hundred twenty-two".