40138781904 has 80 divisors (see below), whose sum is σ = 124075739200. Its totient is φ = 12350392704.

The previous prime is 40138781887. The next prime is 40138781929. The reversal of 40138781904 is 40918783104.

It is a happy number.

40138781904 is a `hidden beast` number, since 401 + 3 + 87 + 81 + 90 + 4 = 666.

It is a super-2 number, since 2×40138781904² (a number of 22 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 40138781904.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3567994 + ... + 3579225.

It is an arithmetic number, because the mean of its divisors is an integer number (1550946740).

Almost surely, 2^40138781904 is an apocalyptic number.

It is an amenable number.

40138781904 is an abundant number, since it is smaller than the sum of its proper divisors (83936957296).

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

40138781904 is a wasteful number, since it uses less digits than its factorization.

40138781904 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7147249 (or 7147237 counting only the distinct ones).

The product of its (nonzero) digits is 193536, while the sum is 45.

The spelling of 40138781904 in words is "forty billion, one hundred thirty-eight million, seven hundred eighty-one thousand, nine hundred four".