51513961 has 6 divisors (see below), whose sum is σ = 54722750. Its totient is φ = 48483456.

The previous prime is 51513949. The next prime is 51513977. The reversal of 51513961 is 16931515.

It can be written as a sum of positive squares in 3 ways, for example, as 35473936 + 16040025 = 5956^2 + 4005^2 .

It is not a de Polignac number, because 51513961 - 2⁵ = 51513929 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (51513901) 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, 88836 + ... + 89413.

Almost surely, 2^51513961 is an apocalyptic number.

It is an amenable number.

51513961 is a deficient number, since it is larger than the sum of its proper divisors (3208789).

51513961 is a wasteful number, since it uses less digits than its factorization.

51513961 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 178283 (or 178266 counting only the distinct ones).

The product of its digits is 4050, while the sum is 31.

The square root of 51513961 is about 7177.3226902516. The cubic root of 51513961 is about 372.0845594377.

The spelling of 51513961 in words is "fifty-one million, five hundred thirteen thousand, nine hundred sixty-one".