20472228 has 36 divisors (see below), whose sum is σ = 59142720. Its totient is φ = 5849136.

The previous prime is 20472223. The next prime is 20472241. The reversal of 20472228 is 82227402.

It is a tau number, because it is divible by the number of its divisors (36).

It is a super-2 number, since 2×20472228² = 838224238567968, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20472223) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 40368 + ... + 40871.

Almost surely, 2^20472228 is an apocalyptic number.

20472228 is a gapful number since it is divisible by the number (28) formed by its first and last digit.

It is an amenable number.

20472228 is an abundant number, since it is smaller than the sum of its proper divisors (38670492).

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

20472228 is a wasteful number, since it uses less digits than its factorization.

20472228 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 81256 (or 81251 counting only the distinct ones).

The product of its (nonzero) digits is 3584, while the sum is 27.

The square root of 20472228 is about 4524.6246253142. The cubic root of 20472228 is about 273.5615378887.

The spelling of 20472228 in words is "twenty million, four hundred seventy-two thousand, two hundred twenty-eight".