51496561 has 4 divisors (see below), whose sum is σ = 51561972. Its totient is φ = 51431152.

The previous prime is 51496507. The next prime is 51496579. The reversal of 51496561 is 16569415.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 16569415 = 5 ⋅3313883.

It can be written as a sum of positive squares in 2 ways, for example, as 19855936 + 31640625 = 4456^2 + 5625^2 .

It is a cyclic number.

It is not a de Polignac number, because 51496561 - 2¹⁵ = 51463793 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 51496561.

It is not an unprimeable number, because it can be changed into a prime (51496591) 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, 31510 + ... + 33103.

It is an arithmetic number, because the mean of its divisors is an integer number (12890493).

Almost surely, 2^51496561 is an apocalyptic number.

It is an amenable number.

51496561 is a deficient number, since it is larger than the sum of its proper divisors (65411).

51496561 is an equidigital number, since it uses as much as digits as its factorization.

51496561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 65410.

The product of its digits is 32400, while the sum is 37.

The square root of 51496561 is about 7176.1104367199. The cubic root of 51496561 is about 372.0426614079.

The spelling of 51496561 in words is "fifty-one million, four hundred ninety-six thousand, five hundred sixty-one".