51530139 has 12 divisors (see below), whose sum is σ = 74568936. Its totient is φ = 34290432.

The previous prime is 51530137. The next prime is 51530161. The reversal of 51530139 is 93103515.

It is not a de Polignac number, because 51530139 - 2¹ = 51530137 is a prime.

It is not an unprimeable number, because it can be changed into a prime (51530131) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 232 + ... + 10154.

It is an arithmetic number, because the mean of its divisors is an integer number (6214078).

Almost surely, 2^51530139 is an apocalyptic number.

51530139 is a deficient number, since it is larger than the sum of its proper divisors (23038797).

51530139 is a wasteful number, since it uses less digits than its factorization.

51530139 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10506 (or 10503 counting only the distinct ones).

The product of its (nonzero) digits is 2025, while the sum is 27.

The square root of 51530139 is about 7178.4496237001. The cubic root of 51530139 is about 372.1235065104.

The spelling of 51530139 in words is "fifty-one million, five hundred thirty thousand, one hundred thirty-nine".