81099315 has 48 divisors (see below), whose sum is σ = 161441280. Its totient is φ = 37247040.

The previous prime is 81099313. The next prime is 81099323. The reversal of 81099315 is 51399018.

It is a happy number.

It is not a de Polignac number, because 81099315 - 2¹ = 81099313 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 81099315.

It is not an unprimeable number, because it can be changed into a prime (81099313) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 5094 + ... + 13716.

It is an arithmetic number, because the mean of its divisors is an integer number (3363360).

Almost surely, 2^81099315 is an apocalyptic number.

81099315 is a deficient number, since it is larger than the sum of its proper divisors (80341965).

81099315 is a wasteful number, since it uses less digits than its factorization.

81099315 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8664 (or 8661 counting only the distinct ones).

The product of its (nonzero) digits is 9720, while the sum is 36.

The square root of 81099315 is about 9005.5158097690. The cubic root of 81099315 is about 432.8516346903.

It can be divided in two parts, 8109 and 9315, that added together give a square (17424 = 132²).

The spelling of 81099315 in words is "eighty-one million, ninety-nine thousand, three hundred fifteen".