81694233 has 24 divisors (see below), whose sum is σ = 120519360. Its totient is φ = 53313120.

The previous prime is 81694211. The next prime is 81694241. The reversal of 81694233 is 33249618.

It is not a de Polignac number, because 81694233 - 2⁵ = 81694201 is a prime.

It is not an unprimeable number, because it can be changed into a prime (81694033) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 110178 + ... + 110916.

It is an arithmetic number, because the mean of its divisors is an integer number (5021640).

Almost surely, 2^81694233 is an apocalyptic number.

It is an amenable number.

81694233 is a deficient number, since it is larger than the sum of its proper divisors (38825127).

81694233 is a wasteful number, since it uses less digits than its factorization.

81694233 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 989 (or 986 counting only the distinct ones).

The product of its digits is 31104, while the sum is 36.

The square root of 81694233 is about 9038.4862117503. The cubic root of 81694233 is about 433.9074763654.

The spelling of 81694233 in words is "eighty-one million, six hundred ninety-four thousand, two hundred thirty-three".