21125635231536 has 120 divisors (see below), whose sum is σ = 67301430932736. Its totient is φ = 6123372520320.

The previous prime is 21125635231529. The next prime is 21125635231541. The reversal of 21125635231536 is 63513253652112.

21125635231536 is a `hidden beast` number, since 2 + 1 + 1 + 2 + 5 + 63 + 52 + 3 + 1 + 536 = 666.

It is a junction number, because it is equal to n+sod(n) for n = 21125635231491 and 21125635231500.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 289895980 + ... + 289968843.

Almost surely, 2^{21125635231536} is an apocalyptic number.

It is an amenable number.

21125635231536 is an abundant number, since it is smaller than the sum of its proper divisors (46175795701200).

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

21125635231536 is a wasteful number, since it uses less digits than its factorization.

21125635231536 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 579864871 (or 579864862 counting only the distinct ones).

The product of its digits is 972000, while the sum is 45.

Adding to 21125635231536 its reverse (63513253652112), we get a palindrome (84638888883648).

The spelling of 21125635231536 in words is "twenty-one trillion, one hundred twenty-five billion, six hundred thirty-five million, two hundred thirty-one thousand, five hundred thirty-six".