81867192 has 64 divisors (see below), whose sum is σ = 227525760. Its totient is φ = 24336000.

The previous prime is 81867173. The next prime is 81867259. The reversal of 81867192 is 29176818.

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, 11067 + ... + 16917.

It is an arithmetic number, because the mean of its divisors is an integer number (3555090).

Almost surely, 2^81867192 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 81867192, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (113762880).

81867192 is an abundant number, since it is smaller than the sum of its proper divisors (145658568).

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

81867192 is a wasteful number, since it uses less digits than its factorization.

81867192 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5924 (or 5920 counting only the distinct ones).

The product of its digits is 48384, while the sum is 42.

The square root of 81867192 is about 9048.0490714850. The cubic root of 81867192 is about 434.2134763521.

The spelling of 81867192 in words is "eighty-one million, eight hundred sixty-seven thousand, one hundred ninety-two".