21677533820 has 12 divisors (see below), whose sum is σ = 45522821064. Its totient is φ = 8671013520.

The previous prime is 21677533819. The next prime is 21677533849. The reversal of 21677533820 is 2833577612.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 541938326 + ... + 541938365.

It is an arithmetic number, because the mean of its divisors is an integer number (3793568422).

Almost surely, 2^21677533820 is an apocalyptic number.

21677533820 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21677533820 is an abundant number, since it is smaller than the sum of its proper divisors (23845287244).

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

21677533820 is a wasteful number, since it uses less digits than its factorization.

21677533820 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1083876700 (or 1083876698 counting only the distinct ones).

The product of its (nonzero) digits is 423360, while the sum is 44.

The spelling of 21677533820 in words is "twenty-one billion, six hundred seventy-seven million, five hundred thirty-three thousand, eight hundred twenty".