818642493 has 24 divisors (see below), whose sum is σ = 1245909600. Its totient is φ = 516543264.

The previous prime is 818642483. The next prime is 818642549. The reversal of 818642493 is 394246818.

It is a happy number.

818642493 is a `hidden beast` number, since 81 + 86 + 4 + 2 + 493 = 666.

It is not a de Polignac number, because 818642493 - 2⁹ = 818641981 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (818642483) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 275371 + ... + 278327.

It is an arithmetic number, because the mean of its divisors is an integer number (51912900).

Almost surely, 2^818642493 is an apocalyptic number.

It is an amenable number.

818642493 is a deficient number, since it is larger than the sum of its proper divisors (427267107).

818642493 is a wasteful number, since it uses less digits than its factorization.

818642493 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4601 (or 4598 counting only the distinct ones).

The product of its digits is 331776, while the sum is 45.

The square root of 818642493 is about 28611.9292079370. The cubic root of 818642493 is about 935.4733675954.

The spelling of 818642493 in words is "eight hundred eighteen million, six hundred forty-two thousand, four hundred ninety-three".