21731727040 has 56 divisors (see below), whose sum is σ = 52121074320. Its totient is φ = 8630135808.

The previous prime is 21731727029. The next prime is 21731727133. The reversal of 21731727040 is 4072713712.

It is a junction number, because it is equal to n+sod(n) for n = 21731726987 and 21731727005.

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, 199807 + ... + 288766.

It is an arithmetic number, because the mean of its divisors is an integer number (930733470).

Almost surely, 2^21731727040 is an apocalyptic number.

21731727040 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21731727040 is an abundant number, since it is smaller than the sum of its proper divisors (30389347280).

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

21731727040 is a wasteful number, since it uses less digits than its factorization.

21731727040 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 488729 (or 488719 counting only the distinct ones).

The product of its (nonzero) digits is 16464, while the sum is 34.

The spelling of 21731727040 in words is "twenty-one billion, seven hundred thirty-one million, seven hundred twenty-seven thousand, forty".