51322661 has 4 divisors (see below), whose sum is σ = 55270572. Its totient is φ = 47374752.

The previous prime is 51322627. The next prime is 51322681. The reversal of 51322661 is 16622315.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 27984100 + 23338561 = 5290^2 + 4831^2 .

It is a cyclic number.

It is not a de Polignac number, because 51322661 - 2⁶ = 51322597 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 51322661.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51322681) 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, 1973936 + ... + 1973961.

It is an arithmetic number, because the mean of its divisors is an integer number (13817643).

Almost surely, 2^51322661 is an apocalyptic number.

It is an amenable number.

51322661 is a deficient number, since it is larger than the sum of its proper divisors (3947911).

51322661 is a wasteful number, since it uses less digits than its factorization.

51322661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3947910.

The product of its digits is 2160, while the sum is 26.

The square root of 51322661 is about 7163.9835985295. The cubic root of 51322661 is about 371.6234024548.

Adding to 51322661 its reverse (16622315), we get a palindrome (67944976).

The spelling of 51322661 in words is "fifty-one million, three hundred twenty-two thousand, six hundred sixty-one".