81254691 has 24 divisors (see below), whose sum is σ = 140033040. Its totient is φ = 46430496.

The previous prime is 81254687. The next prime is 81254707. The reversal of 81254691 is 19645218.

It is not a de Polignac number, because 81254691 - 2² = 81254687 is a prime.

It is not an unprimeable number, because it can be changed into a prime (81254291) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 29386 + ... + 32031.

It is an arithmetic number, because the mean of its divisors is an integer number (5834710).

Almost surely, 2^81254691 is an apocalyptic number.

81254691 is a deficient number, since it is larger than the sum of its proper divisors (58778349).

81254691 is a wasteful number, since it uses less digits than its factorization.

81254691 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 61440 (or 61427 counting only the distinct ones).

The product of its digits is 17280, while the sum is 36.

The square root of 81254691 is about 9014.1383947663. The cubic root of 81254691 is about 433.1278879514.

The spelling of 81254691 in words is "eighty-one million, two hundred fifty-four thousand, six hundred ninety-one".