12521139918 has 32 divisors (see below), whose sum is σ = 28982031360. Its totient is φ = 3532183200.

The previous prime is 12521139853. The next prime is 12521139923. The reversal of 12521139918 is 81993112521.

12521139918 is digitally balanced in base 5, because in such base it contains all the possibile digits an equal number of times.

It is a super-2 number, since 2×12521139918² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is a self number, because there is not a number n which added to its sum of digits gives 12521139918.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1883533 + ... + 1890168.

It is an arithmetic number, because the mean of its divisors is an integer number (905688480).

Almost surely, 2^12521139918 is an apocalyptic number.

12521139918 is an abundant number, since it is smaller than the sum of its proper divisors (16460891442).

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

12521139918 is a wasteful number, since it uses less digits than its factorization.

12521139918 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3773792.

The product of its digits is 38880, while the sum is 42.

The spelling of 12521139918 in words is "twelve billion, five hundred twenty-one million, one hundred thirty-nine thousand, nine hundred eighteen".