20813420 has 12 divisors (see below), whose sum is σ = 43708224. Its totient is φ = 8325360.

The previous prime is 20813399. The next prime is 20813447. The reversal of 20813420 is 2431802.

It is a Harshad number since it is a multiple of its sum of digits (20), and also a Moran number because the ratio is a prime number: 1040671 = 20813420 / (2 + 0 + 8 + 1 + 3 + 4 + 2 + 0).

It is a junction number, because it is equal to n+sod(n) for n = 20813392 and 20813401.

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, 520316 + ... + 520355.

It is an arithmetic number, because the mean of its divisors is an integer number (3642352).

Almost surely, 2^20813420 is an apocalyptic number.

20813420 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20813420 is an abundant number, since it is smaller than the sum of its proper divisors (22894804).

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

20813420 is a wasteful number, since it uses less digits than its factorization.

20813420 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1040680 (or 1040678 counting only the distinct ones).

The product of its (nonzero) digits is 384, while the sum is 20.

The square root of 20813420 is about 4562.1727279883. The cubic root of 20813420 is about 275.0729062897.

The spelling of 20813420 in words is "twenty million, eight hundred thirteen thousand, four hundred twenty".