21321849860 has 48 divisors (see below), whose sum is σ = 45749733120. Its totient is φ = 8343413760.

The previous prime is 21321849847. The next prime is 21321849889. The reversal of 21321849860 is 6894812312.

It is a happy number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2854811 + ... + 2862269.

It is an arithmetic number, because the mean of its divisors is an integer number (953119440).

Almost surely, 2^21321849860 is an apocalyptic number.

21321849860 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21321849860 is an abundant number, since it is smaller than the sum of its proper divisors (24427883260).

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

21321849860 is a wasteful number, since it uses less digits than its factorization.

21321849860 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10556 (or 10554 counting only the distinct ones).

The product of its (nonzero) digits is 165888, while the sum is 44.

The spelling of 21321849860 in words is "twenty-one billion, three hundred twenty-one million, eight hundred forty-nine thousand, eight hundred sixty".