81744694 has 4 divisors (see below), whose sum is σ = 122617044. Its totient is φ = 40872346.

The previous prime is 81744667. The next prime is 81744701. The reversal of 81744694 is 49644718.

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

It is a self number, because there is not a number n which added to its sum of digits gives 81744694.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 20436172 + ... + 20436175.

It is an arithmetic number, because the mean of its divisors is an integer number (30654261).

Almost surely, 2^81744694 is an apocalyptic number.

81744694 is a deficient number, since it is larger than the sum of its proper divisors (40872350).

81744694 is a wasteful number, since it uses less digits than its factorization.

81744694 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 40872349.

The product of its digits is 193536, while the sum is 43.

The square root of 81744694 is about 9041.2772327808. The cubic root of 81744694 is about 433.9967968220.

The spelling of 81744694 in words is "eighty-one million, seven hundred forty-four thousand, six hundred ninety-four".