81022816 has 48 divisors (see below), whose sum is σ = 193034016. Its totient is φ = 32679936.

The previous prime is 81022807. The next prime is 81022817. The reversal of 81022816 is 61822018.

It is a Harshad number since it is a multiple of its sum of digits (28).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81022817) 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, 6831 + ... + 14446.

It is an arithmetic number, because the mean of its divisors is an integer number (4021542).

Almost surely, 2^81022816 is an apocalyptic number.

It is an amenable number.

81022816 is an abundant number, since it is smaller than the sum of its proper divisors (112011200).

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

81022816 is a wasteful number, since it uses less digits than its factorization.

81022816 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21311 (or 21303 counting only the distinct ones).

The product of its (nonzero) digits is 1536, while the sum is 28.

The square root of 81022816 is about 9001.2674663072. The cubic root of 81022816 is about 432.7154924219.

The spelling of 81022816 in words is "eighty-one million, twenty-two thousand, eight hundred sixteen".