642031992 has 96 divisors (see below), whose sum is σ = 2041010400. Its totient is φ = 178474752.

The previous prime is 642031991. The next prime is 642032023. The reversal of 642031992 is 299130246.

642031992 is a `hidden beast` number, since 642 + 0 + 3 + 1 + 9 + 9 + 2 = 666.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (642031991) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1434 + ... + 35862.

It is an arithmetic number, because the mean of its divisors is an integer number (21260525).

Almost surely, 2^642031992 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 642031992, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1020505200).

642031992 is an abundant number, since it is smaller than the sum of its proper divisors (1398978408).

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

642031992 is a wasteful number, since it uses less digits than its factorization.

642031992 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 34485 (or 34478 counting only the distinct ones).

The product of its (nonzero) digits is 23328, while the sum is 36.

The square root of 642031992 is about 25338.3502225382. The cubic root of 642031992 is about 862.6849529008.

The spelling of 642031992 in words is "six hundred forty-two million, thirty-one thousand, nine hundred ninety-two".