20213228 has 24 divisors (see below), whose sum is σ = 42185472. Its totient is φ = 8285904.

The previous prime is 20213197. The next prime is 20213233. The reversal of 20213228 is 82231202.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 15050 + ... + 16337.

It is an arithmetic number, because the mean of its divisors is an integer number (1757728).

Almost surely, 2^20213228 is an apocalyptic number.

20213228 is a gapful number since it is divisible by the number (28) formed by its first and last digit.

It is an amenable number.

20213228 is an abundant number, since it is smaller than the sum of its proper divisors (21972244).

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

20213228 is a wasteful number, since it uses less digits than its factorization.

20213228 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 31421 (or 31419 counting only the distinct ones).

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

The square root of 20213228 is about 4495.9123656940. The cubic root of 20213228 is about 272.4030033817.

The spelling of 20213228 in words is "twenty million, two hundred thirteen thousand, two hundred twenty-eight".