83121581 has 2 divisors, whose sum is σ = 83121582. Its totient is φ = 83121580.

The previous prime is 83121541. The next prime is 83121601. The reversal of 83121581 is 18512138.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 78605956 + 4515625 = 8866^2 + 2125^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-83121581 is a prime.

It is a super-2 number, since 2×83121581² = 13818394455879122, which contains 22 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (83121541) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 41560790 + 41560791.

It is an arithmetic number, because the mean of its divisors is an integer number (41560791).

Almost surely, 2^83121581 is an apocalyptic number.

It is an amenable number.

83121581 is a deficient number, since it is larger than the sum of its proper divisors (1).

83121581 is an equidigital number, since it uses as much as digits as its factorization.

83121581 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1920, while the sum is 29.

The square root of 83121581 is about 9117.1037616120. The cubic root of 83121581 is about 436.4199531574.

The spelling of 83121581 in words is "eighty-three million, one hundred twenty-one thousand, five hundred eighty-one".