81842545 has 16 divisors (see below), whose sum is σ = 101071872. Its totient is φ = 63584640.

The previous prime is 81842521. The next prime is 81842549. The reversal of 81842545 is 54524818.

It is not a de Polignac number, because 81842545 - 2⁵ = 81842513 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (81842549) 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, 40069 + ... + 42061.

It is an arithmetic number, because the mean of its divisors is an integer number (6316992).

Almost surely, 2^81842545 is an apocalyptic number.

It is an amenable number.

81842545 is a deficient number, since it is larger than the sum of its proper divisors (19229327).

81842545 is a wasteful number, since it uses less digits than its factorization.

81842545 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2232.

The product of its digits is 51200, while the sum is 37.

The square root of 81842545 is about 9046.6869626400. The cubic root of 81842545 is about 434.1698970970.

The spelling of 81842545 in words is "eighty-one million, eight hundred forty-two thousand, five hundred forty-five".