51521713 has 4 divisors (see below), whose sum is σ = 54552420. Its totient is φ = 48491008.

The previous prime is 51521689. The next prime is 51521737. The reversal of 51521713 is 31712515.

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

It is an interprime number because it is at equal distance from previous prime (51521689) and next prime (51521737).

It can be written as a sum of positive squares in 2 ways, for example, as 25887744 + 25633969 = 5088^2 + 5063^2 .

It is a cyclic number.

It is not a de Polignac number, because 51521713 - 2⁹ = 51521201 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (51521753) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1515328 + ... + 1515361.

It is an arithmetic number, because the mean of its divisors is an integer number (13638105).

Almost surely, 2^51521713 is an apocalyptic number.

It is an amenable number.

51521713 is a deficient number, since it is larger than the sum of its proper divisors (3030707).

51521713 is a wasteful number, since it uses less digits than its factorization.

51521713 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3030706.

The product of its digits is 1050, while the sum is 25.

The square root of 51521713 is about 7177.8627041759. The cubic root of 51521713 is about 372.1032226943.

The spelling of 51521713 in words is "fifty-one million, five hundred twenty-one thousand, seven hundred thirteen".