139487391 has 6 divisors (see below), whose sum is σ = 201481800. Its totient is φ = 92991588.

The previous prime is 139487389. The next prime is 139487423. The reversal of 139487391 is 193784931.

139487391 is a `hidden beast` number, since 139 + 487 + 39 + 1 = 666.

It is not a de Polignac number, because 139487391 - 2¹ = 139487389 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (139487791) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 7749291 + ... + 7749308.

It is an arithmetic number, because the mean of its divisors is an integer number (33580300).

Almost surely, 2^139487391 is an apocalyptic number.

139487391 is a deficient number, since it is larger than the sum of its proper divisors (61994409).

139487391 is a wasteful number, since it uses less digits than its factorization.

139487391 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15498605 (or 15498602 counting only the distinct ones).

The product of its digits is 163296, while the sum is 45.

The square root of 139487391 is about 11810.4780174216. The cubic root of 139487391 is about 518.6148924576.

The spelling of 139487391 in words is "one hundred thirty-nine million, four hundred eighty-seven thousand, three hundred ninety-one".