139287247 has 16 divisors (see below), whose sum is σ = 158505984. Its totient is φ = 121248000.

The previous prime is 139287229. The next prime is 139287251. The reversal of 139287247 is 742782931.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-139287247 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (139287227) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 30972 + ... + 35182.

It is an arithmetic number, because the mean of its divisors is an integer number (9906624).

Almost surely, 2^139287247 is an apocalyptic number.

139287247 is a deficient number, since it is larger than the sum of its proper divisors (19218737).

139287247 is a wasteful number, since it uses less digits than its factorization.

139287247 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4350.

The product of its digits is 169344, while the sum is 43.

The square root of 139287247 is about 11802.0018217250. The cubic root of 139287247 is about 518.3667282264.

Subtracting from 139287247 its sum of digits (43), we obtain a square (139287204 = 11802²).

The spelling of 139287247 in words is "one hundred thirty-nine million, two hundred eighty-seven thousand, two hundred forty-seven".