642400038720 has 336 divisors, whose sum is σ = 2411551509120. Its totient is φ = 155662848000.

The previous prime is 642400038697. The next prime is 642400038737. The reversal of 642400038720 is 27830004246.

642400038720 is a `hidden beast` number, since 642 + 4 + 0 + 0 + 0 + 3 + 8 + 7 + 2 + 0 = 666.

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 117244941 + ... + 117250419.

Almost surely, 2^642400038720 is an apocalyptic number.

642400038720 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 642400038720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1205775754560).

642400038720 is an abundant number, since it is smaller than the sum of its proper divisors (1769151470400).

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

642400038720 is a wasteful number, since it uses less digits than its factorization.

642400038720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9214 (or 9201 counting only the distinct ones).

The product of its (nonzero) digits is 64512, while the sum is 36.

The spelling of 642400038720 in words is "six hundred forty-two billion, four hundred million, thirty-eight thousand, seven hundred twenty".