18489595820 has 24 divisors (see below), whose sum is σ = 39486258000. Its totient is φ = 7270484672.

The previous prime is 18489595769. The next prime is 18489595823. The reversal of 18489595820 is 2859598481.

It is a super-2 number, since 2×18489595820² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (59).

It is a self number, because there is not a number n which added to its sum of digits gives 18489595820.

It is not an unprimeable number, because it can be changed into a prime (18489595823) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 7833395 + ... + 7835754.

It is an arithmetic number, because the mean of its divisors is an integer number (1645260750).

Almost surely, 2^18489595820 is an apocalyptic number.

18489595820 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

18489595820 is an abundant number, since it is smaller than the sum of its proper divisors (20996662180).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

18489595820 is a wasteful number, since it uses less digits than its factorization.

18489595820 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15669217 (or 15669215 counting only the distinct ones).

The product of its (nonzero) digits is 8294400, while the sum is 59.

The spelling of 18489595820 in words is "eighteen billion, four hundred eighty-nine million, five hundred ninety-five thousand, eight hundred twenty".