81898255 has 4 divisors (see below), whose sum is σ = 98277912. Its totient is φ = 65518600.

The previous prime is 81898253. The next prime is 81898259. The reversal of 81898255 is 55289818.

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

It is not a de Polignac number, because 81898255 - 2¹ = 81898253 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 (81898253) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8189821 + ... + 8189830.

It is an arithmetic number, because the mean of its divisors is an integer number (24569478).

Almost surely, 2^81898255 is an apocalyptic number.

81898255 is a deficient number, since it is larger than the sum of its proper divisors (16379657).

81898255 is a wasteful number, since it uses less digits than its factorization.

81898255 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16379656.

The product of its digits is 230400, while the sum is 46.

The square root of 81898255 is about 9049.7654665743. The cubic root of 81898255 is about 434.2683875130.

The spelling of 81898255 in words is "eighty-one million, eight hundred ninety-eight thousand, two hundred fifty-five".