81858004 has 12 divisors (see below), whose sum is σ = 150791200. Its totient is φ = 38774808.

The previous prime is 81857899. The next prime is 81858013. The reversal of 81858004 is 40085818.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 538464 + ... + 538615.

Almost surely, 2^81858004 is an apocalyptic number.

It is an amenable number.

81858004 is a deficient number, since it is larger than the sum of its proper divisors (68933196).

81858004 is a wasteful number, since it uses less digits than its factorization.

81858004 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1077102 (or 1077100 counting only the distinct ones).

The product of its (nonzero) digits is 10240, while the sum is 34.

The square root of 81858004 is about 9047.5413234757. The cubic root of 81858004 is about 434.1972317386.

The spelling of 81858004 in words is "eighty-one million, eight hundred fifty-eight thousand, four".