21631454601540 has 48 divisors (see below), whose sum is σ = 69220654726272. Its totient is φ = 4944332480256.

The previous prime is 21631454601539. The next prime is 21631454601553. The reversal of 21631454601540 is 4510645413612.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is a junction number, because it is equal to n+sod(n) for n = 21631454601492 and 21631454601501.

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, 25751731249 + ... + 25751732088.

It is an arithmetic number, because the mean of its divisors is an integer number (1442096973464).

Almost surely, 2^{21631454601540} is an apocalyptic number.

21631454601540 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21631454601540 is an abundant number, since it is smaller than the sum of its proper divisors (47589200124732).

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

21631454601540 is a wasteful number, since it uses less digits than its factorization.

21631454601540 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 51503463356 (or 51503463354 counting only the distinct ones).

The product of its (nonzero) digits is 345600, while the sum is 42.

The spelling of 21631454601540 in words is "twenty-one trillion, six hundred thirty-one billion, four hundred fifty-four million, six hundred one thousand, five hundred forty".