642635155120 has 40 divisors (see below), whose sum is σ = 1707573413664. Its totient is φ = 220332052992.

The previous prime is 642635155117. The next prime is 642635155121. The reversal of 642635155120 is 21551536246.

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

It is a super-2 number, since 2×642635155120² (a number of 24 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (40).

It is not an unprimeable number, because it can be changed into a prime (642635155121) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 573780829 + ... + 573781948.

Almost surely, 2^642635155120 is an apocalyptic number.

It is an amenable number.

642635155120 is an abundant number, since it is smaller than the sum of its proper divisors (1064938258544).

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

642635155120 is a wasteful number, since it uses less digits than its factorization.

642635155120 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1147562797 (or 1147562791 counting only the distinct ones).

The product of its (nonzero) digits is 216000, while the sum is 40.

The spelling of 642635155120 in words is "six hundred forty-two billion, six hundred thirty-five million, one hundred fifty-five thousand, one hundred twenty".