21887827656 has 32 divisors (see below), whose sum is σ = 54723236640. Its totient is φ = 7295453568.

The previous prime is 21887827649. The next prime is 21887827697. The reversal of 21887827656 is 65672878812.

It is a self number, because there is not a number n which added to its sum of digits gives 21887827656.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 603180 + ... + 638436.

It is an arithmetic number, because the mean of its divisors is an integer number (1710101145).

Almost surely, 2^21887827656 is an apocalyptic number.

It is an amenable number.

21887827656 is an abundant number, since it is smaller than the sum of its proper divisors (32835408984).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21887827656 is a wasteful number, since it uses less digits than its factorization.

21887827656 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 61133 (or 61129 counting only the distinct ones).

The product of its digits is 18063360, while the sum is 60.

The spelling of 21887827656 in words is "twenty-one billion, eight hundred eighty-seven million, eight hundred twenty-seven thousand, six hundred fifty-six".