138256624 has 20 divisors (see below), whose sum is σ = 292224600. Its totient is φ = 62843840.

The previous prime is 138256603. The next prime is 138256627. The reversal of 138256624 is 426652831.

It is a super-2 number, since 2×138256624² = 38229788159754752, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (138256627) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 392599 + ... + 392950.

It is an arithmetic number, because the mean of its divisors is an integer number (14611230).

Almost surely, 2^138256624 is an apocalyptic number.

It is an amenable number.

138256624 is an abundant number, since it is smaller than the sum of its proper divisors (153967976).

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

138256624 is a wasteful number, since it uses less digits than its factorization.

138256624 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 785568 (or 785562 counting only the distinct ones).

The product of its digits is 69120, while the sum is 37.

The square root of 138256624 is about 11758.2576940634. The cubic root of 138256624 is about 517.0850512365.

It can be divided in two parts, 13825 and 6624, that added together give a square (20449 = 143²).

The spelling of 138256624 in words is "one hundred thirty-eight million, two hundred fifty-six thousand, six hundred twenty-four".