81698412 has 24 divisors (see below), whose sum is σ = 192088512. Its totient is φ = 27024400.

The previous prime is 81698359. The next prime is 81698429. The reversal of 81698412 is 21489618.

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, 24414 + ... + 27557.

It is an arithmetic number, because the mean of its divisors is an integer number (8003688).

Almost surely, 2^81698412 is an apocalyptic number.

It is an amenable number.

81698412 is an abundant number, since it is smaller than the sum of its proper divisors (110390100).

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

81698412 is a wasteful number, since it uses less digits than its factorization.

81698412 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 52109 (or 52107 counting only the distinct ones).

The product of its digits is 27648, while the sum is 39.

The square root of 81698412 is about 9038.7173868863. The cubic root of 81698412 is about 433.9148749637.

The spelling of 81698412 in words is "eighty-one million, six hundred ninety-eight thousand, four hundred twelve".