21251123110044 has 72 divisors (see below), whose sum is σ = 55693103822720. Its totient is φ = 6825265545600.

The previous prime is 21251123110001. The next prime is 21251123110057. The reversal of 21251123110044 is 44001132115212.

21251123110044 is a `hidden beast` number, since 2 + 1 + 2 + 511 + 2 + 3 + 1 + 100 + 44 = 666.

It is a super-2 number, since 2×21251123110044² (a number of 27 digits) contains 22 as substring.

It is a congruent number.

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, 41321347 + ... + 41832474.

Almost surely, 2^{21251123110044} is an apocalyptic number.

It is an amenable number.

21251123110044 is an abundant number, since it is smaller than the sum of its proper divisors (34441980712676).

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

21251123110044 is a wasteful number, since it uses less digits than its factorization.

21251123110044 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 83154091 (or 83154086 counting only the distinct ones).

The product of its (nonzero) digits is 1920, while the sum is 27.

Adding to 21251123110044 its reverse (44001132115212), we get a palindrome (65252255225256).

The spelling of 21251123110044 in words is "twenty-one trillion, two hundred fifty-one billion, one hundred twenty-three million, one hundred ten thousand, forty-four".