21890977936 has 45 divisors (see below), whose sum is σ = 43390524819. Its totient is φ = 10698994272.

The previous prime is 21890977921. The next prime is 21890977939. The reversal of 21890977936 is 63977909812.

The square root of 21890977936 is 147956.

It is a perfect power (a square), and thus also a powerful number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21890977939) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 27815335 + ... + 27816121.

Almost surely, 2^21890977936 is an apocalyptic number.

21890977936 is the 147956-th square number.

It is an amenable number.

21890977936 is a deficient number, since it is larger than the sum of its proper divisors (21499546883).

21890977936 is an frugal number, since it uses more digits than its factorization.

21890977936 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1676 (or 836 counting only the distinct ones).

The product of its (nonzero) digits is 10287648, while the sum is 61.

The spelling of 21890977936 in words is "twenty-one billion, eight hundred ninety million, nine hundred seventy-seven thousand, nine hundred thirty-six".