7909631621 has 4 divisors (see below), whose sum is σ = 8253528672. Its totient is φ = 7565734572.

The previous prime is 7909631579. The next prime is 7909631623. The reversal of 7909631621 is 1261369097.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-7909631621 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (7909631623) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 171948491 + ... + 171948536.

It is an arithmetic number, because the mean of its divisors is an integer number (2063382168).

Almost surely, 2^7909631621 is an apocalyptic number.

It is an amenable number.

7909631621 is a deficient number, since it is larger than the sum of its proper divisors (343897051).

7909631621 is a wasteful number, since it uses less digits than its factorization.

7909631621 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 343897050.

The product of its (nonzero) digits is 122472, while the sum is 44.

The square root of 7909631621 is about 88936.1097698792. The cubic root of 7909631621 is about 1992.4407667421.

The spelling of 7909631621 in words is "seven billion, nine hundred nine million, six hundred thirty-one thousand, six hundred twenty-one".