81698814 has 32 divisors (see below), whose sum is σ = 185986080. Its totient is φ = 26568000.

The previous prime is 81698807. The next prime is 81698863. The reversal of 81698814 is 41889618.

It is a self number, because there is not a number n which added to its sum of digits gives 81698814.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 16237 + ... + 20664.

It is an arithmetic number, because the mean of its divisors is an integer number (5812065).

Almost surely, 2^81698814 is an apocalyptic number.

81698814 is an abundant number, since it is smaller than the sum of its proper divisors (104287266).

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

81698814 is a wasteful number, since it uses less digits than its factorization.

81698814 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 36953 (or 36947 counting only the distinct ones).

The product of its digits is 110592, while the sum is 45.

The square root of 81698814 is about 9038.7396245273. The cubic root of 81698814 is about 433.9155866605.

The spelling of 81698814 in words is "eighty-one million, six hundred ninety-eight thousand, eight hundred fourteen".