81197412 has 24 divisors (see below), whose sum is σ = 199432800. Its totient is φ = 25641216.

The previous prime is 81197411. The next prime is 81197437. The reversal of 81197412 is 21479118.

It is not an unprimeable number, because it can be changed into a prime (81197411) 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, 177837 + ... + 178292.

It is an arithmetic number, because the mean of its divisors is an integer number (8309700).

Almost surely, 2^81197412 is an apocalyptic number.

It is an amenable number.

81197412 is an abundant number, since it is smaller than the sum of its proper divisors (118235388).

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

81197412 is a wasteful number, since it uses less digits than its factorization.

81197412 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 356155 (or 356153 counting only the distinct ones).

The product of its digits is 4032, while the sum is 33.

The square root of 81197412 is about 9010.9606591084. The cubic root of 81197412 is about 433.0260888476.

The spelling of 81197412 in words is "eighty-one million, one hundred ninety-seven thousand, four hundred twelve".