81892310857 has 8 divisors (see below), whose sum is σ = 96610284032. Its totient is φ = 67929105600.

The previous prime is 81892310833. The next prime is 81892310893. The reversal of 81892310857 is 75801329818.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 81892310857 - 2⁷ = 81892310729 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (81892310827) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 188691744 + ... + 188692177.

It is an arithmetic number, because the mean of its divisors is an integer number (12076285504).

Almost surely, 2^81892310857 is an apocalyptic number.

It is an amenable number.

81892310857 is a deficient number, since it is larger than the sum of its proper divisors (14717973175).

81892310857 is a wasteful number, since it uses less digits than its factorization.

81892310857 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 377383959.

The product of its (nonzero) digits is 967680, while the sum is 52.

The spelling of 81892310857 in words is "eighty-one billion, eight hundred ninety-two million, three hundred ten thousand, eight hundred fifty-seven".