21521554142112 has 96 divisors (see below), whose sum is σ = 62812203572160. Its totient is φ = 7169165210880.

The previous prime is 21521554142083. The next prime is 21521554142129. The reversal of 21521554142112 is 21124145512512.

21521554142112 is a `hidden beast` number, since 2 + 1 + 5 + 21 + 5 + 5 + 414 + 211 + 2 = 666.

It is a tau number, because it is divible by the number of its divisors (96).

It is a Harshad number since it is a multiple of its sum of digits (36).

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, 6812163 + ... + 9457730.

It is an arithmetic number, because the mean of its divisors is an integer number (654293787210).

Almost surely, 2^{21521554142112} is an apocalyptic number.

It is an amenable number.

21521554142112 is an abundant number, since it is smaller than the sum of its proper divisors (41290649430048).

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

21521554142112 is a wasteful number, since it uses less digits than its factorization.

21521554142112 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16271443 (or 16271429 counting only the distinct ones).

The product of its digits is 32000, while the sum is 36.

Adding to 21521554142112 its reverse (21124145512512), we get a palindrome (42645699654624).

The spelling of 21521554142112 in words is "twenty-one trillion, five hundred twenty-one billion, five hundred fifty-four million, one hundred forty-two thousand, one hundred twelve".