82861891 has 12 divisors (see below), whose sum is σ = 96542040. Its totient is φ = 70912800.

The previous prime is 82861873. The next prime is 82861921. The reversal of 82861891 is 19816828.

It is not a de Polignac number, because 82861891 - 2¹⁷ = 82730819 is a prime.

It is not an unprimeable number, because it can be changed into a prime (82861811) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 50695 + ... + 52303.

It is an arithmetic number, because the mean of its divisors is an integer number (8045170).

Almost surely, 2^82861891 is an apocalyptic number.

82861891 is a deficient number, since it is larger than the sum of its proper divisors (13680149).

82861891 is a wasteful number, since it uses less digits than its factorization.

82861891 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2674 (or 2667 counting only the distinct ones).

The product of its digits is 55296, while the sum is 43.

The square root of 82861891 is about 9102.8507073334. The cubic root of 82861891 is about 435.9649885614.

The spelling of 82861891 in words is "eighty-two million, eight hundred sixty-one thousand, eight hundred ninety-one".