51649313 has 2 divisors, whose sum is σ = 51649314. Its totient is φ = 51649312.

The previous prime is 51649291. The next prime is 51649387. The reversal of 51649313 is 31394615.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 51595489 + 53824 = 7183^2 + 232^2 .

It is a cyclic number.

It is not a de Polignac number, because 51649313 - 2¹⁴ = 51632929 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 51649313.

It is not a weakly prime, because it can be changed into another prime (51649393) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25824656 + 25824657.

It is an arithmetic number, because the mean of its divisors is an integer number (25824657).

Almost surely, 2^51649313 is an apocalyptic number.

It is an amenable number.

51649313 is a deficient number, since it is larger than the sum of its proper divisors (1).

51649313 is an equidigital number, since it uses as much as digits as its factorization.

51649313 is an evil number, because the sum of its binary digits is even.

The product of its digits is 9720, while the sum is 32.

The square root of 51649313 is about 7186.7456473706. The cubic root of 51649313 is about 372.4101562521.

The spelling of 51649313 in words is "fifty-one million, six hundred forty-nine thousand, three hundred thirteen".