51500521 has 4 divisors (see below), whose sum is σ = 51531844. Its totient is φ = 51469200.

The previous prime is 51500503. The next prime is 51500539. The reversal of 51500521 is 12500515.

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 (51500503) and next prime (51500539).

It can be written as a sum of positive squares in 2 ways, for example, as 13505625 + 37994896 = 3675^2 + 6164^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-51500521 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (51570521) 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, 13050 + ... + 16531.

It is an arithmetic number, because the mean of its divisors is an integer number (12882961).

It is a Poulet number, since it divides 2^51500520-1.

Almost surely, 2^51500521 is an apocalyptic number.

It is an amenable number.

51500521 is a deficient number, since it is larger than the sum of its proper divisors (31323).

51500521 is a wasteful number, since it uses less digits than its factorization.

51500521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 31322.

The product of its (nonzero) digits is 250, while the sum is 19.

The square root of 51500521 is about 7176.3863469019. The cubic root of 51500521 is about 372.0521976510.

The spelling of 51500521 in words is "fifty-one million, five hundred thousand, five hundred twenty-one".