81552057 has 4 divisors (see below), whose sum is σ = 108736080. Its totient is φ = 54368036.

The previous prime is 81552049. The next prime is 81552061. The reversal of 81552057 is 75025518.

It is a happy number.

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 81552057 - 2³ = 81552049 is a prime.

It is not an unprimeable number, because it can be changed into a prime (81552017) 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, 13592007 + ... + 13592012.

It is an arithmetic number, because the mean of its divisors is an integer number (27184020).

Almost surely, 2^81552057 is an apocalyptic number.

It is an amenable number.

81552057 is a deficient number, since it is larger than the sum of its proper divisors (27184023).

81552057 is a wasteful number, since it uses less digits than its factorization.

81552057 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 27184022.

The product of its (nonzero) digits is 14000, while the sum is 33.

The square root of 81552057 is about 9030.6177529558. The cubic root of 81552057 is about 433.6556142298.

The spelling of 81552057 in words is "eighty-one million, five hundred fifty-two thousand, fifty-seven".