81137359 has 2 divisors, whose sum is σ = 81137360. Its totient is φ = 81137358.

The previous prime is 81137347. The next prime is 81137363. The reversal of 81137359 is 95373118.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-81137359 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (81137159) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40568679 + 40568680.

It is an arithmetic number, because the mean of its divisors is an integer number (40568680).

Almost surely, 2^81137359 is an apocalyptic number.

81137359 is a deficient number, since it is larger than the sum of its proper divisors (1).

81137359 is an equidigital number, since it uses as much as digits as its factorization.

81137359 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 22680, while the sum is 37.

The square root of 81137359 is about 9007.6278231286. The cubic root of 81137359 is about 432.9193082306.

The spelling of 81137359 in words is "eighty-one million, one hundred thirty-seven thousand, three hundred fifty-nine".