642341664 has 120 divisors (see below), whose sum is σ = 1988688240. Its totient is φ = 202829184.

The previous prime is 642341659. The next prime is 642341701. The reversal of 642341664 is 466143246.

642341664 is a `hidden beast` number, since 642 + 3 + 4 + 1 + 6 + 6 + 4 = 666.

It is a super-3 number, since 3×642341664³ (a number of 27 digits) contains 333 as substring.

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

It is a nude number because it is divisible by every one of its digits.

It is an unprimeable number.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 42727 + ... + 55769.

It is an arithmetic number, because the mean of its divisors is an integer number (16572402).

Almost surely, 2^642341664 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 642341664, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (994344120).

642341664 is an abundant number, since it is smaller than the sum of its proper divisors (1346346576).

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

642341664 is a wasteful number, since it uses less digits than its factorization.

642341664 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13084 (or 13067 counting only the distinct ones).

The product of its digits is 82944, while the sum is 36.

The square root of 642341664 is about 25344.4602230941. The cubic root of 642341664 is about 862.8236305358.

The spelling of 642341664 in words is "six hundred forty-two million, three hundred forty-one thousand, six hundred sixty-four".