138647806 has 32 divisors (see below), whose sum is σ = 236390400. Its totient is φ = 60429600.

The previous prime is 138647783. The next prime is 138647809. The reversal of 138647806 is 608746831.

138647806 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a super-2 number, since 2×138647806² = 38446428217227272, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (138647809) 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, 56595 + ... + 58993.

It is an arithmetic number, because the mean of its divisors is an integer number (7387200).

Almost surely, 2^138647806 is an apocalyptic number.

138647806 is a deficient number, since it is larger than the sum of its proper divisors (97742594).

138647806 is a wasteful number, since it uses less digits than its factorization.

138647806 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2520.

The product of its (nonzero) digits is 193536, while the sum is 43.

The square root of 138647806 is about 11774.8802966315. The cubic root of 138647806 is about 517.5722705511.

The spelling of 138647806 in words is "one hundred thirty-eight million, six hundred forty-seven thousand, eight hundred six".