81457243 has 12 divisors (see below), whose sum is σ = 96201840. Its totient is φ = 67562640.

The previous prime is 81457219. The next prime is 81457247. The reversal of 81457243 is 34275418.

It is not a de Polignac number, because 81457243 - 2¹⁷ = 81326171 is a prime.

It is a super-2 number, since 2×81457243² = 13270564874322098, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 81457199 and 81457208.

It is not an unprimeable number, because it can be changed into a prime (81457247) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 673 + ... + 12781.

It is an arithmetic number, because the mean of its divisors is an integer number (8016820).

Almost surely, 2^81457243 is an apocalyptic number.

81457243 is a deficient number, since it is larger than the sum of its proper divisors (14744597).

81457243 is a wasteful number, since it uses less digits than its factorization.

81457243 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12178 (or 12147 counting only the distinct ones).

The product of its digits is 26880, while the sum is 34.

The square root of 81457243 is about 9025.3666407521. The cubic root of 81457243 is about 433.4874902546.

The spelling of 81457243 in words is "eighty-one million, four hundred fifty-seven thousand, two hundred forty-three".