81655427 has 16 divisors (see below), whose sum is σ = 95232000. Its totient is φ = 68571360.

The previous prime is 81655421. The next prime is 81655429. The reversal of 81655427 is 72455618.

It is a cyclic number.

It is not a de Polignac number, because 81655427 - 2⁶ = 81655363 is a prime.

It is a super-3 number, since 3×81655427³ (a number of 25 digits) contains 333 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (81655421) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 81902 + ... + 82892.

It is an arithmetic number, because the mean of its divisors is an integer number (5952000).

Almost surely, 2^81655427 is an apocalyptic number.

81655427 is a deficient number, since it is larger than the sum of its proper divisors (13576573).

81655427 is a wasteful number, since it uses less digits than its factorization.

81655427 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1226.

The product of its digits is 67200, while the sum is 38.

The square root of 81655427 is about 9036.3392477264. The cubic root of 81655427 is about 433.8387612728.

The spelling of 81655427 in words is "eighty-one million, six hundred fifty-five thousand, four hundred twenty-seven".