21252101112 has 64 divisors (see below), whose sum is σ = 64400313600. Its totient is φ = 6440029920.

The previous prime is 21252101053. The next prime is 21252101153. The reversal of 21252101112 is 21110125212.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a congruent number.

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, 4469868 + ... + 4474619.

It is an arithmetic number, because the mean of its divisors is an integer number (1006254900).

Almost surely, 2^21252101112 is an apocalyptic number.

21252101112 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

It is an amenable number.

21252101112 is an abundant number, since it is smaller than the sum of its proper divisors (43148212488).

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

21252101112 is a wasteful number, since it uses less digits than its factorization.

21252101112 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8944513 (or 8944503 counting only the distinct ones).

The product of its (nonzero) digits is 80, while the sum is 18.

Adding to 21252101112 its reverse (21110125212), we get a palindrome (42362226324).

The spelling of 21252101112 in words is "twenty-one billion, two hundred fifty-two million, one hundred one thousand, one hundred twelve".