642032720 has 40 divisors (see below), whose sum is σ = 1705974144. Its totient is φ = 220125312.

The previous prime is 642032719. The next prime is 642032731. The reversal of 642032720 is 27230246.

It is a tau number, because it is divible by the number of its divisors (40).

It is a self number, because there is not a number n which added to its sum of digits gives 642032720.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 572684 + ... + 573803.

Almost surely, 2^642032720 is an apocalyptic number.

It is an amenable number.

642032720 is an abundant number, since it is smaller than the sum of its proper divisors (1063941424).

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

642032720 is a wasteful number, since it uses less digits than its factorization.

642032720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1146507 (or 1146501 counting only the distinct ones).

The product of its (nonzero) digits is 4032, while the sum is 26.

The square root of 642032720 is about 25338.3645881103. The cubic root of 642032720 is about 862.6852789668.

Adding to 642032720 its reverse (27230246), we get a palindrome (669262966).

The spelling of 642032720 in words is "six hundred forty-two million, thirty-two thousand, seven hundred twenty".