18420605840 has 160 divisors (see below), whose sum is σ = 52903447296. Its totient is φ = 5808568320.

The previous prime is 18420605789. The next prime is 18420605851. The reversal of 18420605840 is 4850602481.

It is a happy number.

It is a junction number, because it is equal to n+sod(n) for n = 18420605794 and 18420605803.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 2055770 + ... + 2064710.

Almost surely, 2^18420605840 is an apocalyptic number.

18420605840 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 18420605840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (26451723648).

18420605840 is an abundant number, since it is smaller than the sum of its proper divisors (34482841456).

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

18420605840 is a wasteful number, since it uses less digits than its factorization.

18420605840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9257 (or 9251 counting only the distinct ones).

The product of its (nonzero) digits is 61440, while the sum is 38.

The spelling of 18420605840 in words is "eighteen billion, four hundred twenty million, six hundred five thousand, eight hundred forty".