20456220 has 24 divisors (see below), whose sum is σ = 57277584. Its totient is φ = 5454976.

The previous prime is 20456209. The next prime is 20456221. The reversal of 20456220 is 2265402.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20456221) 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, 170409 + ... + 170528.

It is an arithmetic number, because the mean of its divisors is an integer number (2386566).

Almost surely, 2^20456220 is an apocalyptic number.

20456220 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20456220 is an abundant number, since it is smaller than the sum of its proper divisors (36821364).

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

20456220 is a wasteful number, since it uses less digits than its factorization.

20456220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 340949 (or 340947 counting only the distinct ones).

The product of its (nonzero) digits is 960, while the sum is 21.

The square root of 20456220 is about 4522.8552928432. The cubic root of 20456220 is about 273.4902166333.

The spelling of 20456220 in words is "twenty million, four hundred fifty-six thousand, two hundred twenty".