21406632314544 has 80 divisors (see below), whose sum is σ = 61753732032000. Its totient is φ = 7099687070784.

The previous prime is 21406632314531. The next prime is 21406632314563. The reversal of 21406632314544 is 44541323660412.

21406632314544 is a `hidden beast` number, since 2 + 1 + 4 + 0 + 6 + 632 + 3 + 1 + 4 + 5 + 4 + 4 = 666.

It is a self number, because there is not a number n which added to its sum of digits gives 21406632314544.

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, 124417524 + ... + 124589459.

It is an arithmetic number, because the mean of its divisors is an integer number (771921650400).

Almost surely, 2^{21406632314544} is an apocalyptic number.

21406632314544 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

21406632314544 is an abundant number, since it is smaller than the sum of its proper divisors (40347099717456).

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

21406632314544 is a wasteful number, since it uses less digits than its factorization.

21406632314544 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 249007199 (or 249007187 counting only the distinct ones).

The product of its (nonzero) digits is 1658880, while the sum is 45.

Adding to 21406632314544 its reverse (44541323660412), we get a palindrome (65947955974956).

The spelling of 21406632314544 in words is "twenty-one trillion, four hundred six billion, six hundred thirty-two million, three hundred fourteen thousand, five hundred forty-four".