81308453 has 8 divisors (see below), whose sum is σ = 84537600. Its totient is φ = 78138720.

The previous prime is 81308411. The next prime is 81308477. The reversal of 81308453 is 35480318.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 81308453 - 2²⁰ = 80259877 is a prime.

It is a super-2 number, since 2×81308453² = 13222129058506418, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81308653) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 12053 + ... + 17546.

It is an arithmetic number, because the mean of its divisors is an integer number (10567200).

Almost surely, 2^81308453 is an apocalyptic number.

It is an amenable number.

81308453 is a deficient number, since it is larger than the sum of its proper divisors (3229147).

81308453 is a wasteful number, since it uses less digits than its factorization.

81308453 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 29707.

The product of its (nonzero) digits is 11520, while the sum is 32.

The square root of 81308453 is about 9017.1199947655. The cubic root of 81308453 is about 433.2233929511.

The spelling of 81308453 in words is "eighty-one million, three hundred eight thousand, four hundred fifty-three".