81256198 has 8 divisors (see below), whose sum is σ = 128299320. Its totient is φ = 38489760.

The previous prime is 81256183. The next prime is 81256213. The reversal of 81256198 is 89165218.

It is an interprime number because it is at equal distance from previous prime (81256183) and next prime (81256213).

It is a sphenic number, since it is the product of 3 distinct primes.

It is a self number, because there is not a number n which added to its sum of digits gives 81256198.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1069123 + ... + 1069198.

It is an arithmetic number, because the mean of its divisors is an integer number (16037415).

Almost surely, 2^81256198 is an apocalyptic number.

81256198 is a deficient number, since it is larger than the sum of its proper divisors (47043122).

81256198 is a wasteful number, since it uses less digits than its factorization.

81256198 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2138342.

The product of its digits is 34560, while the sum is 40.

The square root of 81256198 is about 9014.2219852853. The cubic root of 81256198 is about 433.1305656211.

The spelling of 81256198 in words is "eighty-one million, two hundred fifty-six thousand, one hundred ninety-eight".