139661538 has 16 divisors (see below), whose sum is σ = 279501600. Its totient is φ = 46524096.

The previous prime is 139661521. The next prime is 139661563. The reversal of 139661538 is 835166931.

It is a happy number.

It is a self number, because there is not a number n which added to its sum of digits gives 139661538.

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, 4113 + ... + 17211.

It is an arithmetic number, because the mean of its divisors is an integer number (17468850).

Almost surely, 2^139661538 is an apocalyptic number.

139661538 is an abundant number, since it is smaller than the sum of its proper divisors (139840062).

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

139661538 is a wasteful number, since it uses less digits than its factorization.

139661538 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14881.

The product of its digits is 116640, while the sum is 42.

The square root of 139661538 is about 11817.8482813074. The cubic root of 139661538 is about 518.8306292052.

The spelling of 139661538 in words is "one hundred thirty-nine million, six hundred sixty-one thousand, five hundred thirty-eight".