20213920 has 24 divisors (see below), whose sum is σ = 47755764. Its totient is φ = 8085504.

The previous prime is 20213887. The next prime is 20213923. The reversal of 20213920 is 2931202.

20213920 = T₁₅ + T₁₆ + ... + T₄₉₄.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 19678096 + 535824 = 4436^2 + 732^2 .

It is not an unprimeable number, because it can be changed into a prime (20213923) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 63009 + ... + 63328.

Almost surely, 2^20213920 is an apocalyptic number.

20213920 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20213920 is an abundant number, since it is smaller than the sum of its proper divisors (27541844).

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

20213920 is a wasteful number, since it uses less digits than its factorization.

20213920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 126352 (or 126344 counting only the distinct ones).

The product of its (nonzero) digits is 216, while the sum is 19.

The square root of 20213920 is about 4495.9893238307. The cubic root of 20213920 is about 272.4061119191.

The spelling of 20213920 in words is "twenty million, two hundred thirteen thousand, nine hundred twenty".