138558740 has 24 divisors (see below), whose sum is σ = 292253640. Its totient is φ = 55179648.

The previous prime is 138558737. The next prime is 138558767. The reversal of 138558740 is 47855831.

It can be written as a sum of positive squares in 4 ways, for example, as 81072016 + 57486724 = 9004^2 + 7582^2 .

It is a congruent number.

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, 10547 + ... + 19706.

It is an arithmetic number, because the mean of its divisors is an integer number (12177235).

Almost surely, 2^138558740 is an apocalyptic number.

138558740 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

138558740 is an abundant number, since it is smaller than the sum of its proper divisors (153694900).

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

138558740 is a wasteful number, since it uses less digits than its factorization.

138558740 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 30491 (or 30489 counting only the distinct ones).

The product of its (nonzero) digits is 134400, while the sum is 41.

The square root of 138558740 is about 11771.0976548494. The cubic root of 138558740 is about 517.4614190161.

The spelling of 138558740 in words is "one hundred thirty-eight million, five hundred fifty-eight thousand, seven hundred forty".