15620718961 has 4 divisors (see below), whose sum is σ = 15661504512. Its totient is φ = 15579933412.

The previous prime is 15620718857. The next prime is 15620718973. The reversal of 15620718961 is 16981702651.

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 not a de Polignac number, because 15620718961 - 2¹⁹ = 15620194673 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (15620718361) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 20392201 + ... + 20392966.

It is an arithmetic number, because the mean of its divisors is an integer number (3915376128).

Almost surely, 2^15620718961 is an apocalyptic number.

It is an amenable number.

15620718961 is a deficient number, since it is larger than the sum of its proper divisors (40785551).

15620718961 is an equidigital number, since it uses as much as digits as its factorization.

15620718961 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 40785550.

The product of its (nonzero) digits is 181440, while the sum is 46.

The spelling of 15620718961 in words is "fifteen billion, six hundred twenty million, seven hundred eighteen thousand, nine hundred sixty-one".