18942420 has 144 divisors (see below), whose sum is σ = 65499840. Its totient is φ = 4064256.

The previous prime is 18942419. The next prime is 18942439. The reversal of 18942420 is 2424981.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 49791 + ... + 50169.

It is an arithmetic number, because the mean of its divisors is an integer number (454860).

Almost surely, 2^18942420 is an apocalyptic number.

18942420 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 18942420, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (32749920).

18942420 is an abundant number, since it is smaller than the sum of its proper divisors (46557420).

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

18942420 is a wasteful number, since it uses less digits than its factorization.

18942420 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 422 (or 413 counting only the distinct ones).

The product of its (nonzero) digits is 4608, while the sum is 30.

The square root of 18942420 is about 4352.2890529008. The cubic root of 18942420 is about 266.5703367340.

The spelling of 18942420 in words is "eighteen million, nine hundred forty-two thousand, four hundred twenty".