43687137521664 has 2496 divisors, whose sum is σ = 172686934425600. Its totient is φ = 10787380789248.

The previous prime is 43687137521659. The next prime is 43687137521737. The reversal of 43687137521664 is 46612573178634.

43687137521664 is a `hidden beast` number, since 4 + 3 + 6 + 8 + 71 + 37 + 521 + 6 + 6 + 4 = 666.

It is a tau number, because it is divible by the number of its divisors (2496).

It is a Harshad number since it is a multiple of its sum of digits (63).

It is an unprimeable number.

It is a polite number, since it can be written in 191 ways as a sum of consecutive naturals, for example, 169988861824 + ... + 169988862080.

Almost surely, 2^{43687137521664} is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 43687137521664, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (86343467212800).

43687137521664 is an abundant number, since it is smaller than the sum of its proper divisors (128999796903936).

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

43687137521664 is a wasteful number, since it uses less digits than its factorization.

43687137521664 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 463 (or 428 counting only the distinct ones).

The product of its digits is 121927680, while the sum is 63.

The spelling of 43687137521664 in words is "forty-three trillion, six hundred eighty-seven billion, one hundred thirty-seven million, five hundred twenty-one thousand, six hundred sixty-four".