51520901 has 6 divisors (see below), whose sum is σ = 51820902. Its totient is φ = 51222600.

The previous prime is 51520891. The next prime is 51520927. The reversal of 51520901 is 10902515.

It can be written as a sum of positive squares in only one way, i.e., 26770276 + 24750625 = 5174^2 + 4975^2 .

It is a de Polignac number, because none of the positive numbers 2^k-51520901 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51520961) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 38951 + ... + 40251.

It is an arithmetic number, because the mean of its divisors is an integer number (8636817).

Almost surely, 2^51520901 is an apocalyptic number.

It is an amenable number.

51520901 is a deficient number, since it is larger than the sum of its proper divisors (300001).

51520901 is an equidigital number, since it uses as much as digits as its factorization.

51520901 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1699 (or 1500 counting only the distinct ones).

The product of its (nonzero) digits is 450, while the sum is 23.

The square root of 51520901 is about 7177.8061411548. The cubic root of 51520901 is about 372.1012678590.

The spelling of 51520901 in words is "fifty-one million, five hundred twenty thousand, nine hundred one".