81122369 has 2 divisors, whose sum is σ = 81122370. Its totient is φ = 81122368.

The previous prime is 81122347. The next prime is 81122387. The reversal of 81122369 is 96322118.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 75777025 + 5345344 = 8705^2 + 2312^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-81122369 is a prime.

It is a super-2 number, since 2×81122369² = 13161677504344322, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (81122869) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40561184 + 40561185.

It is an arithmetic number, because the mean of its divisors is an integer number (40561185).

Almost surely, 2^81122369 is an apocalyptic number.

It is an amenable number.

81122369 is a deficient number, since it is larger than the sum of its proper divisors (1).

81122369 is an equidigital number, since it uses as much as digits as its factorization.

81122369 is an evil number, because the sum of its binary digits is even.

The product of its digits is 5184, while the sum is 32.

The square root of 81122369 is about 9006.7957121276. The cubic root of 81122369 is about 432.8926462005.

The spelling of 81122369 in words is "eighty-one million, one hundred twenty-two thousand, three hundred sixty-nine".