81892911 has 4 divisors (see below), whose sum is σ = 109190552. Its totient is φ = 54595272.

The previous prime is 81892879. The next prime is 81892913. The reversal of 81892911 is 11929818.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 81892911 - 2⁵ = 81892879 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 81892911.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81892913) 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, 13648816 + ... + 13648821.

It is an arithmetic number, because the mean of its divisors is an integer number (27297638).

Almost surely, 2^81892911 is an apocalyptic number.

81892911 is a deficient number, since it is larger than the sum of its proper divisors (27297641).

81892911 is a wasteful number, since it uses less digits than its factorization.

81892911 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 27297640.

The product of its digits is 10368, while the sum is 39.

The square root of 81892911 is about 9049.4702054872. The cubic root of 81892911 is about 434.2589417247.

The spelling of 81892911 in words is "eighty-one million, eight hundred ninety-two thousand, nine hundred eleven".