51615971 has 4 divisors (see below), whose sum is σ = 56308344. Its totient is φ = 46923600.

The previous prime is 51615959. The next prime is 51616009. The reversal of 51615971 is 17951615.

It is a happy number.

51615971 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-51615971 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (51615901) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2346170 + ... + 2346191.

It is an arithmetic number, because the mean of its divisors is an integer number (14077086).

Almost surely, 2^51615971 is an apocalyptic number.

51615971 is a deficient number, since it is larger than the sum of its proper divisors (4692373).

51615971 is a wasteful number, since it uses less digits than its factorization.

51615971 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4692372.

The product of its digits is 9450, while the sum is 35.

The square root of 51615971 is about 7184.4255859463. The cubic root of 51615971 is about 372.3300030577.

The spelling of 51615971 in words is "fifty-one million, six hundred fifteen thousand, nine hundred seventy-one".