20228440 has 16 divisors (see below), whose sum is σ = 45514080. Its totient is φ = 8091360.

The previous prime is 20228437. The next prime is 20228449. The reversal of 20228440 is 4482202.

It is a super-3 number, since 3×20228440³ (a number of 23 digits) contains 333 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20228449) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 252816 + ... + 252895.

It is an arithmetic number, because the mean of its divisors is an integer number (2844630).

Almost surely, 2^20228440 is an apocalyptic number.

20228440 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20228440 is an abundant number, since it is smaller than the sum of its proper divisors (25285640).

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

20228440 is a wasteful number, since it uses less digits than its factorization.

20228440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 505722 (or 505718 counting only the distinct ones).

The product of its (nonzero) digits is 1024, while the sum is 22.

The square root of 20228440 is about 4497.6038064730. The cubic root of 20228440 is about 272.4713209444.

The spelling of 20228440 in words is "twenty million, two hundred twenty-eight thousand, four hundred forty".