81460191 has 4 divisors (see below), whose sum is σ = 108613592. Its totient is φ = 54306792.

The previous prime is 81460147. The next prime is 81460241. The reversal of 81460191 is 19106418.

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

It is not a de Polignac number, because 81460191 - 2¹⁷ = 81329119 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 (81462191) 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, 13576696 + ... + 13576701.

It is an arithmetic number, because the mean of its divisors is an integer number (27153398).

Almost surely, 2^81460191 is an apocalyptic number.

81460191 is a deficient number, since it is larger than the sum of its proper divisors (27153401).

81460191 is a wasteful number, since it uses less digits than its factorization.

81460191 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 27153400.

The product of its (nonzero) digits is 1728, while the sum is 30.

The square root of 81460191 is about 9025.5299567394. The cubic root of 81460191 is about 433.4927196062.

The spelling of 81460191 in words is "eighty-one million, four hundred sixty thousand, one hundred ninety-one".