51715217 has 4 divisors (see below), whose sum is σ = 52369920. Its totient is φ = 51060516.

The previous prime is 51715199. The next prime is 51715231. The reversal of 51715217 is 71251715.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 51715217 - 2²⁰ = 50666641 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 51715217.

It is not an unprimeable number, because it can be changed into a prime (51715267) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 327233 + ... + 327390.

It is an arithmetic number, because the mean of its divisors is an integer number (13092480).

Almost surely, 2^51715217 is an apocalyptic number.

It is an amenable number.

51715217 is a deficient number, since it is larger than the sum of its proper divisors (654703).

51715217 is an equidigital number, since it uses as much as digits as its factorization.

51715217 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 654702.

The product of its digits is 2450, while the sum is 29.

The square root of 51715217 is about 7191.3292929750. The cubic root of 51715217 is about 372.5684861240.

The spelling of 51715217 in words is "fifty-one million, seven hundred fifteen thousand, two hundred seventeen".