13644631620 has 72 divisors (see below), whose sum is σ = 41406840384. Its totient is φ = 3636975168.

The previous prime is 13644631603. The next prime is 13644631639. The reversal of 13644631620 is 2613644631.

13644631620 is a `hidden beast` number, since 1 + 3 + 644 + 6 + 3 + 1 + 6 + 2 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

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, 428697 + ... + 459423.

Almost surely, 2^13644631620 is an apocalyptic number.

13644631620 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

13644631620 is an abundant number, since it is smaller than the sum of its proper divisors (27762208764).

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

13644631620 is a wasteful number, since it uses less digits than its factorization.

13644631620 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 33209 (or 33204 counting only the distinct ones).

The product of its (nonzero) digits is 62208, while the sum is 36.

The spelling of 13644631620 in words is "thirteen billion, six hundred forty-four million, six hundred thirty-one thousand, six hundred twenty".