13129406821638 has 24 divisors (see below), whose sum is σ = 28449057780000. Its totient is φ = 4376159761104.

The previous prime is 13129406821633. The next prime is 13129406821639. The reversal of 13129406821638 is 83612860492131.

It is a happy number.

13129406821638 is a `hidden beast` number, since 1 + 3 + 12 + 9 + 406 + 8 + 216 + 3 + 8 = 666.

13129406821638 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (13129406821633) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 25503013 + ... + 26012736.

It is an arithmetic number, because the mean of its divisors is an integer number (1185377407500).

Almost surely, 2^{13129406821638} is an apocalyptic number.

13129406821638 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

13129406821638 is an abundant number, since it is smaller than the sum of its proper divisors (15319650958362).

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

13129406821638 is a wasteful number, since it uses less digits than its factorization.

13129406821638 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 51529916 (or 51529913 counting only the distinct ones).

The product of its (nonzero) digits is 2985984, while the sum is 54.

The spelling of 13129406821638 in words is "thirteen trillion, one hundred twenty-nine billion, four hundred six million, eight hundred twenty-one thousand, six hundred thirty-eight".