1539138868 has 12 divisors (see below), whose sum is σ = 2744314020. Its totient is φ = 755049152.

The previous prime is 1539138823. The next prime is 1539138869. The reversal of 1539138868 is 8688319351.

It can be written as a sum of positive squares in 2 ways, for example, as 1385923984 + 153214884 = 37228^2 + 12378^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1539138869) 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, 3629833 + ... + 3630256.

It is an arithmetic number, because the mean of its divisors is an integer number (228692835).

Almost surely, 2^1539138868 is an apocalyptic number.

It is an amenable number.

1539138868 is a deficient number, since it is larger than the sum of its proper divisors (1205175152).

1539138868 is a wasteful number, since it uses less digits than its factorization.

1539138868 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7260146 (or 7260144 counting only the distinct ones).

The product of its digits is 1244160, while the sum is 52.

The square root of 1539138868 is about 39231.8603688380. The cubic root of 1539138868 is about 1154.5850643721.

The spelling of 1539138868 in words is "one billion, five hundred thirty-nine million, one hundred thirty-eight thousand, eight hundred sixty-eight".