21123025112 has 16 divisors (see below), whose sum is σ = 45263625360. Its totient is φ = 9052725024.

The previous prime is 21123025111. The next prime is 21123025139. The reversal of 21123025112 is 21152032112.

It is a super-2 number, since 2×21123025112² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21123025111) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 188598383 + ... + 188598494.

It is an arithmetic number, because the mean of its divisors is an integer number (2828976585).

Almost surely, 2^21123025112 is an apocalyptic number.

It is an amenable number.

21123025112 is an abundant number, since it is smaller than the sum of its proper divisors (24140600248).

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

21123025112 is a wasteful number, since it uses less digits than its factorization.

21123025112 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 377196890 (or 377196886 counting only the distinct ones).

The product of its (nonzero) digits is 240, while the sum is 20.

Adding to 21123025112 its reverse (21152032112), we get a palindrome (42275057224).

The spelling of 21123025112 in words is "twenty-one billion, one hundred twenty-three million, twenty-five thousand, one hundred twelve".