81892286139 has 4 divisors (see below), whose sum is σ = 109189714856. Its totient is φ = 54594857424.

The previous prime is 81892286131. The next prime is 81892286159. The reversal of 81892286139 is 93168229818.

It is a happy number.

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

It is not a de Polignac number, because 81892286139 - 2³ = 81892286131 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (81892286131) 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, 13648714354 + ... + 13648714359.

It is an arithmetic number, because the mean of its divisors is an integer number (27297428714).

Almost surely, 2^81892286139 is an apocalyptic number.

81892286139 is a deficient number, since it is larger than the sum of its proper divisors (27297428717).

81892286139 is a wasteful number, since it uses less digits than its factorization.

81892286139 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 27297428716.

The product of its digits is 2985984, while the sum is 57.

The spelling of 81892286139 in words is "eighty-one billion, eight hundred ninety-two million, two hundred eighty-six thousand, one hundred thirty-nine".