405887621664 has 96 divisors (see below), whose sum is σ = 1221504713856. Its totient is φ = 115602001920.

The previous prime is 405887621593. The next prime is 405887621669. The reversal of 405887621664 is 466126788504.

It is a tau number, because it is divible by the number of its divisors (96).

It is a super-2 number, since 2×405887621664² (a number of 24 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (405887621669) 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, 739657 + ... + 1165704.

It is an arithmetic number, because the mean of its divisors is an integer number (12724007436).

Almost surely, 2^405887621664 is an apocalyptic number.

It is an amenable number.

405887621664 is an abundant number, since it is smaller than the sum of its proper divisors (815617092192).

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

405887621664 is a wasteful number, since it uses less digits than its factorization.

405887621664 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1905698 (or 1905690 counting only the distinct ones).

The product of its (nonzero) digits is 15482880, while the sum is 57.

The spelling of 405887621664 in words is "four hundred five billion, eight hundred eighty-seven million, six hundred twenty-one thousand, six hundred sixty-four".