405689937138 has 24 divisors (see below), whose sum is σ = 880366175676. Its totient is φ = 135019008000.

The previous prime is 405689937131. The next prime is 405689937179. The reversal of 405689937138 is 831739986504.

405689937138 is a `hidden beast` number, since 4 + 0 + 568 + 9 + 9 + 37 + 1 + 38 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 404606671569 + 1083265569 = 636087^2 + 32913^2 .

It is not an unprimeable number, because it can be changed into a prime (405689937131) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 17569063 + ... + 17592138.

Almost surely, 2^405689937138 is an apocalyptic number.

405689937138 is an abundant number, since it is smaller than the sum of its proper divisors (474676238538).

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

405689937138 is a wasteful number, since it uses less digits than its factorization.

405689937138 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 35161850 (or 35161847 counting only the distinct ones).

The product of its (nonzero) digits is 39191040, while the sum is 63.

The spelling of 405689937138 in words is "four hundred five billion, six hundred eighty-nine million, nine hundred thirty-seven thousand, one hundred thirty-eight".