21163634130645 has 16 divisors (see below), whose sum is σ = 37624238454720. Its totient is φ = 11287271536272.

The previous prime is 21163634130641. The next prime is 21163634130649. The reversal of 21163634130645 is 54603143636112.

21163634130645 is a `hidden beast` number, since 2 + 1 + 1 + 6 + 3 + 634 + 1 + 3 + 0 + 6 + 4 + 5 = 666.

It is an interprime number because it is at equal distance from previous prime (21163634130641) and next prime (21163634130649).

It is not a de Polignac number, because 21163634130645 - 2² = 21163634130641 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a self number, because there is not a number n which added to its sum of digits gives 21163634130645.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21163634130641) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 78383829979 + ... + 78383830248.

It is an arithmetic number, because the mean of its divisors is an integer number (2351514903420).

Almost surely, 2^{21163634130645} is an apocalyptic number.

It is an amenable number.

21163634130645 is a deficient number, since it is larger than the sum of its proper divisors (16460604324075).

21163634130645 is a wasteful number, since it uses less digits than its factorization.

21163634130645 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 156767660241 (or 156767660235 counting only the distinct ones).

The product of its (nonzero) digits is 933120, while the sum is 45.

Adding to 21163634130645 its reverse (54603143636112), we get a palindrome (75766777766757).

The spelling of 21163634130645 in words is "twenty-one trillion, one hundred sixty-three billion, six hundred thirty-four million, one hundred thirty thousand, six hundred forty-five".