81307359 has 12 divisors (see below), whose sum is σ = 134221776. Its totient is φ = 46461312.

The previous prime is 81307337. The next prime is 81307399. The reversal of 81307359 is 95370318.

It is not a de Polignac number, because 81307359 - 2⁸ = 81307103 is a prime.

It is a super-2 number, since 2×81307359² = 13221773255109762, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81307319) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 645234 + ... + 645359.

It is an arithmetic number, because the mean of its divisors is an integer number (11185148).

Almost surely, 2^81307359 is an apocalyptic number.

81307359 is a deficient number, since it is larger than the sum of its proper divisors (52914417).

81307359 is a wasteful number, since it uses less digits than its factorization.

81307359 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1290606 (or 1290603 counting only the distinct ones).

The product of its (nonzero) digits is 22680, while the sum is 36.

The square root of 81307359 is about 9017.0593321770. The cubic root of 81307359 is about 433.2214499448.

The spelling of 81307359 in words is "eighty-one million, three hundred seven thousand, three hundred fifty-nine".