51591517 has 8 divisors (see below), whose sum is σ = 54440960. Its totient is φ = 48755520.

The previous prime is 51591499. The next prime is 51591521. The reversal of 51591517 is 71519515.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a de Polignac number, because none of the positive numbers 2^k-51591517 is a prime.

It is a super-2 number, since 2×51591517² = 5323369252722578, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51591557) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5092 + ... + 11362.

It is an arithmetic number, because the mean of its divisors is an integer number (6805120).

Almost surely, 2^51591517 is an apocalyptic number.

It is an amenable number.

51591517 is a deficient number, since it is larger than the sum of its proper divisors (2849443).

51591517 is a wasteful number, since it uses less digits than its factorization.

51591517 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6723.

The product of its digits is 7875, while the sum is 34.

The square root of 51591517 is about 7182.7235085307. The cubic root of 51591517 is about 372.2711944114.

The spelling of 51591517 in words is "fifty-one million, five hundred ninety-one thousand, five hundred seventeen".