40138686 has 32 divisors (see below), whose sum is σ = 101940480. Its totient is φ = 11468088.

The previous prime is 40138661. The next prime is 40138687. The reversal of 40138686 is 68683104.

It is a happy number.

It is a super-2 number, since 2×40138686² = 3222228227613192, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 40138686.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (40138687) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 52716 + ... + 53471.

It is an arithmetic number, because the mean of its divisors is an integer number (3185640).

Almost surely, 2^40138686 is an apocalyptic number.

40138686 is an abundant number, since it is smaller than the sum of its proper divisors (61801794).

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

40138686 is a wasteful number, since it uses less digits than its factorization.

40138686 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 106205 (or 106199 counting only the distinct ones).

The product of its (nonzero) digits is 27648, while the sum is 36.

The square root of 40138686 is about 6335.5099242287. The cubic root of 40138686 is about 342.3899829569.

The spelling of 40138686 in words is "forty million, one hundred thirty-eight thousand, six hundred eighty-six".