21542421312 has 112 divisors (see below), whose sum is σ = 66664027200. Its totient is φ = 6802859520.

The previous prime is 21542421289. The next prime is 21542421319. The reversal of 21542421312 is 21312424512.

21542421312 is a `hidden beast` number, since 2 + 15 + 424 + 213 + 12 = 666.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21542421319) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 295239 + ... + 360902.

Almost surely, 2^21542421312 is an apocalyptic number.

It is an amenable number.

21542421312 is an abundant number, since it is smaller than the sum of its proper divisors (45121605888).

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

21542421312 is a wasteful number, since it uses less digits than its factorization.

21542421312 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 656181 (or 656165 counting only the distinct ones).

The product of its digits is 3840, while the sum is 27.

Adding to 21542421312 its reverse (21312424512), we get a palindrome (42854845824).

The spelling of 21542421312 in words is "twenty-one billion, five hundred forty-two million, four hundred twenty-one thousand, three hundred twelve".