81436293 has 16 divisors (see below), whose sum is σ = 121182400. Its totient is φ = 54049680.

The previous prime is 81436279. The next prime is 81436319. The reversal of 81436293 is 39263418.

It is not a de Polignac number, because 81436293 - 2¹³ = 81428101 is a prime.

It is a Duffinian number.

It is a plaindrome in base 12.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81436193) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 403 + ... + 12768.

It is an arithmetic number, because the mean of its divisors is an integer number (7573900).

Almost surely, 2^81436293 is an apocalyptic number.

It is an amenable number.

81436293 is a deficient number, since it is larger than the sum of its proper divisors (39746107).

81436293 is a wasteful number, since it uses less digits than its factorization.

81436293 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13409 (or 13403 counting only the distinct ones).

The product of its digits is 31104, while the sum is 36.

The square root of 81436293 is about 9024.2059484478. The cubic root of 81436293 is about 433.4503241649.

The spelling of 81436293 in words is "eighty-one million, four hundred thirty-six thousand, two hundred ninety-three".