138817866 has 16 divisors (see below), whose sum is σ = 302875488. Its totient is φ = 42066000.

The previous prime is 138817859. The next prime is 138817873. The reversal of 138817866 is 668718831.

It is an interprime number because it is at equal distance from previous prime (138817859) and next prime (138817873).

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1051585 + ... + 1051716.

It is an arithmetic number, because the mean of its divisors is an integer number (18929718).

Almost surely, 2^138817866 is an apocalyptic number.

138817866 is an abundant number, since it is smaller than the sum of its proper divisors (164057622).

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

138817866 is a wasteful number, since it uses less digits than its factorization.

138817866 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2103317.

The product of its digits is 387072, while the sum is 48.

The square root of 138817866 is about 11782.0993884791. The cubic root of 138817866 is about 517.7837954230.

The spelling of 138817866 in words is "one hundred thirty-eight million, eight hundred seventeen thousand, eight hundred sixty-six".