81339755 has 12 divisors (see below), whose sum is σ = 113544000. Its totient is φ = 55775664.

The previous prime is 81339733. The next prime is 81339761. The reversal of 81339755 is 55793318.

It is a happy number.

It is not a de Polignac number, because 81339755 - 2⁸ = 81339499 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 165755 + ... + 166244.

It is an arithmetic number, because the mean of its divisors is an integer number (9462000).

Almost surely, 2^81339755 is an apocalyptic number.

81339755 is a deficient number, since it is larger than the sum of its proper divisors (32204245).

81339755 is a wasteful number, since it uses less digits than its factorization.

81339755 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 332018 (or 332011 counting only the distinct ones).

The product of its digits is 113400, while the sum is 41.

The square root of 81339755 is about 9018.8555260632. The cubic root of 81339755 is about 433.2789797047.

The spelling of 81339755 in words is "eighty-one million, three hundred thirty-nine thousand, seven hundred fifty-five".