51395515 has 4 divisors (see below), whose sum is σ = 61674624. Its totient is φ = 41116408.

The previous prime is 51395497. The next prime is 51395521. The reversal of 51395515 is 51559315.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 51395515 - 2¹⁵ = 51362747 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5139547 + ... + 5139556.

It is an arithmetic number, because the mean of its divisors is an integer number (15418656).

Almost surely, 2^51395515 is an apocalyptic number.

51395515 is a deficient number, since it is larger than the sum of its proper divisors (10279109).

51395515 is a wasteful number, since it uses less digits than its factorization.

51395515 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10279108.

The product of its digits is 16875, while the sum is 34.

The square root of 51395515 is about 7169.0665361677. The cubic root of 51395515 is about 371.7991627008.

The spelling of 51395515 in words is "fifty-one million, three hundred ninety-five thousand, five hundred fifteen".