642615536640 has 1408 divisors, whose sum is σ = 2803512508416. Its totient is φ = 121503744000.

The previous prime is 642615536627. The next prime is 642615536687. The reversal of 642615536640 is 46635516246.

642615536640 is digitally balanced in base 2 and base 4, because in such bases it contains all the possibile digits an equal number of times.

It is a tau number, because it is divible by the number of its divisors (1408).

It is a super-2 number, since 2×642615536640² (a number of 24 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (48).

It is a self number, because there is not a number n which added to its sum of digits gives 642615536640.

It is an unprimeable number.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 623292925 + ... + 623293955.

Almost surely, 2^642615536640 is an apocalyptic number.

642615536640 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 642615536640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1401756254208).

642615536640 is an abundant number, since it is smaller than the sum of its proper divisors (2160896971776).

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

642615536640 is a wasteful number, since it uses less digits than its factorization.

642615536640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1125 (or 1107 counting only the distinct ones).

The product of its (nonzero) digits is 3110400, while the sum is 48.

The spelling of 642615536640 in words is "six hundred forty-two billion, six hundred fifteen million, five hundred thirty-six thousand, six hundred forty".