83507581 has 2 divisors, whose sum is σ = 83507582. Its totient is φ = 83507580.

The previous prime is 83507569. The next prime is 83507623. The reversal of 83507581 is 18570538.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 60140025 + 23367556 = 7755^2 + 4834^2 .

It is a cyclic number.

It is not a de Polignac number, because 83507581 - 2⁹ = 83507069 is a prime.

It is a super-2 number, since 2×83507581² = 13947032168943122, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 83507581.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (83507531) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 41753790 + 41753791.

It is an arithmetic number, because the mean of its divisors is an integer number (41753791).

Almost surely, 2^83507581 is an apocalyptic number.

It is an amenable number.

83507581 is a deficient number, since it is larger than the sum of its proper divisors (1).

83507581 is an equidigital number, since it uses as much as digits as its factorization.

83507581 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 33600, while the sum is 37.

The square root of 83507581 is about 9138.2482456979. The cubic root of 83507581 is about 437.0944591386.

It can be divided in two parts, 8350 and 7581, that added together give a triangular number (15931 = T₁₇₈).

The spelling of 83507581 in words is "eighty-three million, five hundred seven thousand, five hundred eighty-one".