624121906 has 4 divisors (see below), whose sum is σ = 936182862. Its totient is φ = 312060952.

The previous prime is 624121871. The next prime is 624121907. The reversal of 624121906 is 609121426.

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., 424154025 + 199967881 = 20595^2 + 14141^2 .

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is not an unprimeable number, because it can be changed into a prime (624121907) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 156030475 + ... + 156030478.

Almost surely, 2^624121906 is an apocalyptic number.

624121906 is a deficient number, since it is larger than the sum of its proper divisors (312060956).

624121906 is a wasteful number, since it uses less digits than its factorization.

624121906 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 312060955.

The product of its (nonzero) digits is 5184, while the sum is 31.

The square root of 624121906 is about 24982.4319472705. The cubic root of 624121906 is about 854.5873804436.

The spelling of 624121906 in words is "six hundred twenty-four million, one hundred twenty-one thousand, nine hundred six".