81048857 has 4 divisors (see below), whose sum is σ = 81079680. Its totient is φ = 81018036.

The previous prime is 81048853. The next prime is 81048883. The reversal of 81048857 is 75884018.

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 81048857 - 2² = 81048853 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (81048853) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 11057 + ... + 16862.

It is an arithmetic number, because the mean of its divisors is an integer number (20269920).

Almost surely, 2^81048857 is an apocalyptic number.

It is an amenable number.

81048857 is a deficient number, since it is larger than the sum of its proper divisors (30823).

81048857 is a wasteful number, since it uses less digits than its factorization.

81048857 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 30822.

The product of its (nonzero) digits is 71680, while the sum is 41.

The square root of 81048857 is about 9002.7138686065. The cubic root of 81048857 is about 432.7618461844.

It can be divided in two parts, 8104 and 8857, that added together give a palindrome (16961).

The spelling of 81048857 in words is "eighty-one million, forty-eight thousand, eight hundred fifty-seven".