40139388 has 30 divisors (see below), whose sum is σ = 104933136. Its totient is φ = 13379688.

The previous prime is 40139371. The next prime is 40139417. The reversal of 40139388 is 88393104.

It is a super-2 number, since 2×40139388² = 3222340938029088, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 61620 + ... + 62267.

Almost surely, 2^40139388 is an apocalyptic number.

It is an amenable number.

40139388 is an abundant number, since it is smaller than the sum of its proper divisors (64793748).

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

40139388 is a wasteful number, since it uses less digits than its factorization.

40139388 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 123903 (or 123892 counting only the distinct ones).

The product of its (nonzero) digits is 20736, while the sum is 36.

The square root of 40139388 is about 6335.5653259989. The cubic root of 40139388 is about 342.3919790061.

The spelling of 40139388 in words is "forty million, one hundred thirty-nine thousand, three hundred eighty-eight".