51512513 has 8 divisors (see below), whose sum is σ = 55543656. Its totient is φ = 47491200.

The previous prime is 51512491. The next prime is 51512557. The reversal of 51512513 is 31521515.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 4631104 + 46881409 = 2152^2 + 6847^2 .

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

It is a cyclic number.

It is not a de Polignac number, because 51512513 - 2²² = 47318209 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (51512563) 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, 11333 + ... + 15213.

It is an arithmetic number, because the mean of its divisors is an integer number (6942957).

Almost surely, 2^51512513 is an apocalyptic number.

It is an amenable number.

51512513 is a deficient number, since it is larger than the sum of its proper divisors (4031143).

51512513 is a wasteful number, since it uses less digits than its factorization.

51512513 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4915.

The product of its digits is 750, while the sum is 23.

The square root of 51512513 is about 7177.2218162740. The cubic root of 51512513 is about 372.0810731110.

It can be divided in two parts, 51512 and 513, that added together give a palindrome (52025).

The spelling of 51512513 in words is "fifty-one million, five hundred twelve thousand, five hundred thirteen".