81183057 has 4 divisors (see below), whose sum is σ = 108244080. Its totient is φ = 54122036.

The previous prime is 81183043. The next prime is 81183059. The reversal of 81183057 is 75038118.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 81183057 - 2²² = 76988753 is a prime.

It is not an unprimeable number, because it can be changed into a prime (81183059) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 13530507 + ... + 13530512.

It is an arithmetic number, because the mean of its divisors is an integer number (27061020).

Almost surely, 2^81183057 is an apocalyptic number.

It is an amenable number.

81183057 is a deficient number, since it is larger than the sum of its proper divisors (27061023).

81183057 is a wasteful number, since it uses less digits than its factorization.

81183057 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 27061022.

The product of its (nonzero) digits is 6720, while the sum is 33.

The square root of 81183057 is about 9010.1640939552. The cubic root of 81183057 is about 433.0005689215. Note that the first 3 decimals are identical.

It can be divided in two parts, 8118 and 3057, that added together give a triangular number (11175 = T₁₄₉).

The spelling of 81183057 in words is "eighty-one million, one hundred eighty-three thousand, fifty-seven".