81545683 has 4 divisors (see below), whose sum is σ = 82353168. Its totient is φ = 80738200.

The previous prime is 81545657. The next prime is 81545687. The reversal of 81545683 is 38654518.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-81545683 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (81545687) 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, 403591 + ... + 403792.

It is an arithmetic number, because the mean of its divisors is an integer number (20588292).

Almost surely, 2^81545683 is an apocalyptic number.

81545683 is a deficient number, since it is larger than the sum of its proper divisors (807485).

81545683 is a wasteful number, since it uses less digits than its factorization.

81545683 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 807484.

The product of its digits is 115200, while the sum is 40.

The square root of 81545683 is about 9030.2648355405. The cubic root of 81545683 is about 433.6443159540.

It can be divided in two parts, 81545 and 683, that added together give a palindrome (82228).

The spelling of 81545683 in words is "eighty-one million, five hundred forty-five thousand, six hundred eighty-three".