81423318 has 16 divisors (see below), whose sum is σ = 163200960. Its totient is φ = 27082056.

The previous prime is 81423301. The next prime is 81423337. The reversal of 81423318 is 81332418.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 11728 + ... + 17331.

It is an arithmetic number, because the mean of its divisors is an integer number (10200060).

Almost surely, 2^81423318 is an apocalyptic number.

81423318 is an abundant number, since it is smaller than the sum of its proper divisors (81777642).

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

81423318 is a wasteful number, since it uses less digits than its factorization.

81423318 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 29531.

The product of its digits is 4608, while the sum is 30.

The square root of 81423318 is about 9023.4870199940. The cubic root of 81423318 is about 433.4273028294.

The spelling of 81423318 in words is "eighty-one million, four hundred twenty-three thousand, three hundred eighteen".