51015961 has 4 divisors (see below), whose sum is σ = 51358500. Its totient is φ = 50673424.

The previous prime is 51015953. The next prime is 51016039. The reversal of 51015961 is 16951015.

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 30030400 + 20985561 = 5480^2 + 4581^2 .

It is a cyclic number.

It is not a de Polignac number, because 51015961 - 2³ = 51015953 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (51015061) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 171046 + ... + 171343.

It is an arithmetic number, because the mean of its divisors is an integer number (12839625).

Almost surely, 2^51015961 is an apocalyptic number.

It is an amenable number.

51015961 is a deficient number, since it is larger than the sum of its proper divisors (342539).

51015961 is a wasteful number, since it uses less digits than its factorization.

51015961 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 342538.

The product of its (nonzero) digits is 1350, while the sum is 28.

The square root of 51015961 is about 7142.5458346447. The cubic root of 51015961 is about 370.8816593278.

Adding to 51015961 its reverse (16951015), we get a palindrome (67966976).

It can be divided in two parts, 510 and 15961, that added together give a triangular number (16471 = T₁₈₁).

The spelling of 51015961 in words is "fifty-one million, fifteen thousand, nine hundred sixty-one".