21607795577 has 8 divisors (see below), whose sum is σ = 22016814792. Its totient is φ = 21200544000.

The previous prime is 21607795541. The next prime is 21607795589. The reversal of 21607795577 is 77559770612.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 6706954816 + 14900840761 = 81896^2 + 122069^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21607795577 - 2²² = 21603601273 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21607795507) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 417218 + ... + 466139.

It is an arithmetic number, because the mean of its divisors is an integer number (2752101849).

Almost surely, 2^21607795577 is an apocalyptic number.

It is an amenable number.

21607795577 is a deficient number, since it is larger than the sum of its proper divisors (409019215).

21607795577 is an equidigital number, since it uses as much as digits as its factorization.

21607795577 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 883819.

The product of its (nonzero) digits is 6482700, while the sum is 56.

The spelling of 21607795577 in words is "twenty-one billion, six hundred seven million, seven hundred ninety-five thousand, five hundred seventy-seven".