81880899 has 8 divisors (see below), whose sum is σ = 114920640. Its totient is φ = 51714216.

The previous prime is 81880873. The next prime is 81880913. The reversal of 81880899 is 99808818.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 81880899 - 2⁵ = 81880867 is a prime.

It is not an unprimeable number, because it can be changed into a prime (81880819) 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 7 ways as a sum of consecutive naturals, for example, 718197 + ... + 718310.

It is an arithmetic number, because the mean of its divisors is an integer number (14365080).

Almost surely, 2^81880899 is an apocalyptic number.

81880899 is a deficient number, since it is larger than the sum of its proper divisors (33039741).

81880899 is a wasteful number, since it uses less digits than its factorization.

81880899 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1436529.

The product of its (nonzero) digits is 331776, while the sum is 51.

The square root of 81880899 is about 9048.8064958866. The cubic root of 81880899 is about 434.2377084115.

The spelling of 81880899 in words is "eighty-one million, eight hundred eighty thousand, eight hundred ninety-nine".