81814724 has 24 divisors (see below), whose sum is σ = 146989920. Its totient is φ = 39824064.

The previous prime is 81814723. The next prime is 81814729. The reversal of 81814724 is 42741818.

It is a Smith number, since the sum of its digits (35) coincides with the sum of the digits of its prime factors.

It is not an unprimeable number, because it can be changed into a prime (81814723) 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, 69767 + ... + 70929.

It is an arithmetic number, because the mean of its divisors is an integer number (6124580).

Almost surely, 2^81814724 is an apocalyptic number.

It is an amenable number.

81814724 is a deficient number, since it is larger than the sum of its proper divisors (65175196).

81814724 is a wasteful number, since it uses less digits than its factorization.

81814724 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1619 (or 1617 counting only the distinct ones).

The product of its digits is 14336, while the sum is 35.

The square root of 81814724 is about 9045.1491972217. The cubic root of 81814724 is about 434.1206952642.

The spelling of 81814724 in words is "eighty-one million, eight hundred fourteen thousand, seven hundred twenty-four".