81746833866 has 64 divisors (see below), whose sum is σ = 169443059328. Its totient is φ = 26280004608.

The previous prime is 81746833781. The next prime is 81746833907. The reversal of 81746833866 is 66833864718.

It is a super-3 number, since 3×81746833866³ (a number of 34 digits) contains 333 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 4010236 + ... + 4030568.

It is an arithmetic number, because the mean of its divisors is an integer number (2647547802).

Almost surely, 2^81746833866 is an apocalyptic number.

81746833866 is an abundant number, since it is smaller than the sum of its proper divisors (87696225462).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

81746833866 is a wasteful number, since it uses less digits than its factorization.

81746833866 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20615.

The product of its digits is 27869184, while the sum is 60.

The spelling of 81746833866 in words is "eighty-one billion, seven hundred forty-six million, eight hundred thirty-three thousand, eight hundred sixty-six".