138729591 has 160 divisors (see below), whose sum is σ = 292723200. Its totient is φ = 63141120.

The previous prime is 138729553. The next prime is 138729599. The reversal of 138729591 is 195927831.

138729591 = 494² + 495² + ... + 812².

138729591 is a `hidden beast` number, since 1 + 38 + 7 + 29 + 591 = 666.

It is not a de Polignac number, because 138729591 - 2¹⁰ = 138728567 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (138729599) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 159 ways as a sum of consecutive naturals, for example, 2351320 + ... + 2351378.

It is an arithmetic number, because the mean of its divisors is an integer number (1829520).

Almost surely, 2^138729591 is an apocalyptic number.

138729591 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

138729591 is an abundant number, since it is smaller than the sum of its proper divisors (153993609).

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

138729591 is a wasteful number, since it uses less digits than its factorization.

138729591 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 131 (or 122 counting only the distinct ones).

The product of its digits is 136080, while the sum is 45.

The square root of 138729591 is about 11778.3526437274. The cubic root of 138729591 is about 517.6740183514.

The spelling of 138729591 in words is "one hundred thirty-eight million, seven hundred twenty-nine thousand, five hundred ninety-one".