21431131000 has 32 divisors (see below), whose sum is σ = 50148848880. Its totient is φ = 8572452000.

The previous prime is 21431130991. The next prime is 21431131021. The reversal of 21431131000 is 13113412.

It is a super-2 number, since 2×21431131000² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

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, 10714566 + ... + 10716565.

Almost surely, 2^21431131000 is an apocalyptic number.

21431131000 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21431131000 is an abundant number, since it is smaller than the sum of its proper divisors (28717717880).

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

21431131000 is a wasteful number, since it uses less digits than its factorization.

21431131000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21431152 (or 21431138 counting only the distinct ones).

The product of its (nonzero) digits is 72, while the sum is 16.

Adding to 21431131000 its reverse (13113412), we get a palindrome (21444244412).

The spelling of 21431131000 in words is "twenty-one billion, four hundred thirty-one million, one hundred thirty-one thousand".