642431026156 has 12 divisors (see below), whose sum is σ = 1124344417168. Its totient is φ = 321189764112.

The previous prime is 642431026121. The next prime is 642431026169. The reversal of 642431026156 is 651620134246.

It is a super-2 number, since 2×642431026156² (a number of 24 digits) contains 22 as substring.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6381051 + ... + 6480946.

Almost surely, 2^642431026156 is an apocalyptic number.

It is an amenable number.

642431026156 is a deficient number, since it is larger than the sum of its proper divisors (481913391012).

642431026156 is a wasteful number, since it uses less digits than its factorization.

642431026156 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12874488 (or 12874486 counting only the distinct ones).

The product of its (nonzero) digits is 207360, while the sum is 40.

The spelling of 642431026156 in words is "six hundred forty-two billion, four hundred thirty-one million, twenty-six thousand, one hundred fifty-six".