5139236521 has 4 divisors (see below), whose sum is σ = 5139548500. Its totient is φ = 5138924544.

The previous prime is 5139236507. The next prime is 5139236563. The reversal of 5139236521 is 1256329315.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1256329315 = 5 ⋅251265863.

It can be written as a sum of positive squares in 2 ways, for example, as 2930706496 + 2208530025 = 54136^2 + 46995^2 .

It is a cyclic number.

It is not a de Polignac number, because 5139236521 - 2³¹ = 2991752873 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (5139236591) 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, 129816 + ... + 164713.

It is an arithmetic number, because the mean of its divisors is an integer number (1284887125).

Almost surely, 2^5139236521 is an apocalyptic number.

It is an amenable number.

5139236521 is a deficient number, since it is larger than the sum of its proper divisors (311979).

5139236521 is a wasteful number, since it uses less digits than its factorization.

5139236521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 311978.

The product of its digits is 48600, while the sum is 37.

The square root of 5139236521 is about 71688.4685357415. The cubic root of 5139236521 is about 1725.7035870724.

The spelling of 5139236521 in words is "five billion, one hundred thirty-nine million, two hundred thirty-six thousand, five hundred twenty-one".