50721581 has 2 divisors, whose sum is σ = 50721582. Its totient is φ = 50721580.

The previous prime is 50721571. The next prime is 50721589. The reversal of 50721581 is 18512705.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 37515625 + 13205956 = 6125^2 + 3634^2 .

It is a cyclic number.

It is not a de Polignac number, because 50721581 - 2¹⁴ = 50705197 is a prime.

It is a super-2 number, since 2×50721581² = 5145357558279122, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (50721589) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25360790 + 25360791.

It is an arithmetic number, because the mean of its divisors is an integer number (25360791).

Almost surely, 2^50721581 is an apocalyptic number.

It is an amenable number.

50721581 is a deficient number, since it is larger than the sum of its proper divisors (1).

50721581 is an equidigital number, since it uses as much as digits as its factorization.

50721581 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2800, while the sum is 29.

The square root of 50721581 is about 7121.9085222993. The cubic root of 50721581 is about 370.1669103282.

The spelling of 50721581 in words is "fifty million, seven hundred twenty-one thousand, five hundred eighty-one".