81038499 has 16 divisors (see below), whose sum is σ = 116640000. Its totient is φ = 49893536.

The previous prime is 81038497. The next prime is 81038521. The reversal of 81038499 is 99483018.

It is a cyclic number.

It is not a de Polignac number, because 81038499 - 2¹ = 81038497 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 81038499.

It is not an unprimeable number, because it can be changed into a prime (81038497) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 18249 + ... + 22250.

It is an arithmetic number, because the mean of its divisors is an integer number (7290000).

Almost surely, 2^81038499 is an apocalyptic number.

81038499 is a deficient number, since it is larger than the sum of its proper divisors (35601501).

81038499 is a wasteful number, since it uses less digits than its factorization.

81038499 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 40554.

The product of its (nonzero) digits is 62208, while the sum is 42.

The square root of 81038499 is about 9002.1385792488. The cubic root of 81038499 is about 432.7434098225.

The spelling of 81038499 in words is "eighty-one million, thirty-eight thousand, four hundred ninety-nine".