81299000 has 32 divisors (see below), whose sum is σ = 190242000. Its totient is φ = 32519200.

The previous prime is 81298999. The next prime is 81299011. The reversal of 81299000 is 99218.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 39650 + ... + 41649.

Almost surely, 2^81299000 is an apocalyptic number.

It is an amenable number.

81299000 is an abundant number, since it is smaller than the sum of its proper divisors (108943000).

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

81299000 is a wasteful number, since it uses less digits than its factorization.

81299000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 81320 (or 81306 counting only the distinct ones).

The product of its (nonzero) digits is 1296, while the sum is 29.

The square root of 81299000 is about 9016.5958099496. The cubic root of 81299000 is about 433.2066033091.

The spelling of 81299000 in words is "eighty-one million, two hundred ninety-nine thousand".