21964446157 has 4 divisors (see below), whose sum is σ = 21986002080. Its totient is φ = 21942890236.

The previous prime is 21964446067. The next prime is 21964446169. The reversal of 21964446157 is 75164446912.

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-21964446157 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21964446157.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21964446457) 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, 10776433 + ... + 10778470.

It is an arithmetic number, because the mean of its divisors is an integer number (5496500520).

Almost surely, 2^21964446157 is an apocalyptic number.

It is an amenable number.

21964446157 is a deficient number, since it is larger than the sum of its proper divisors (21555923).

21964446157 is a wasteful number, since it uses less digits than its factorization.

21964446157 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21555922.

The product of its digits is 1451520, while the sum is 49.

The spelling of 21964446157 in words is "twenty-one billion, nine hundred sixty-four million, four hundred forty-six thousand, one hundred fifty-seven".