81417199 has 4 divisors (see below), whose sum is σ = 86206464. Its totient is φ = 76627936.

The previous prime is 81417187. The next prime is 81417209. The reversal of 81417199 is 99171418.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-81417199 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81417139) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2394607 + ... + 2394640.

It is an arithmetic number, because the mean of its divisors is an integer number (21551616).

Almost surely, 2^81417199 is an apocalyptic number.

81417199 is a deficient number, since it is larger than the sum of its proper divisors (4789265).

81417199 is a wasteful number, since it uses less digits than its factorization.

81417199 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4789264.

The product of its digits is 18144, while the sum is 40.

The square root of 81417199 is about 9023.1479540125. The cubic root of 81417199 is about 433.4164451367.

It can be divided in two parts, 814 and 17199, that multiplied together give a triangular number (13999986 = T₅₂₉₁).

The spelling of 81417199 in words is "eighty-one million, four hundred seventeen thousand, one hundred ninety-nine".