51761581 has 2 divisors, whose sum is σ = 51761582. Its totient is φ = 51761580.

The previous prime is 51761543. The next prime is 51761597. The reversal of 51761581 is 18516715.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 49829481 + 1932100 = 7059^2 + 1390^2 .

It is a cyclic number.

It is not a de Polignac number, because 51761581 - 2¹⁵ = 51728813 is a prime.

It is a super-2 number, since 2×51761581² = 5358522535239122, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (51761531) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25880790 + 25880791.

It is an arithmetic number, because the mean of its divisors is an integer number (25880791).

Almost surely, 2^51761581 is an apocalyptic number.

It is an amenable number.

51761581 is a deficient number, since it is larger than the sum of its proper divisors (1).

51761581 is an equidigital number, since it uses as much as digits as its factorization.

51761581 is an evil number, because the sum of its binary digits is even.

The product of its digits is 8400, while the sum is 34.

The square root of 51761581 is about 7194.5521750836. The cubic root of 51761581 is about 372.6797918913.

The spelling of 51761581 in words is "fifty-one million, seven hundred sixty-one thousand, five hundred eighty-one".