221275420 has 24 divisors (see below), whose sum is σ = 475486704. Its totient is φ = 86451456.

The previous prime is 221275403. The next prime is 221275421. The reversal of 221275420 is 24572122.

It is a super-2 number, since 2×221275420² = 97925622992352800, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221275421) 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, 127789 + ... + 129508.

It is an arithmetic number, because the mean of its divisors is an integer number (19811946).

Almost surely, 2^221275420 is an apocalyptic number.

221275420 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

221275420 is an abundant number, since it is smaller than the sum of its proper divisors (254211284).

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

221275420 is a wasteful number, since it uses less digits than its factorization.

221275420 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 257349 (or 257347 counting only the distinct ones).

The product of its (nonzero) digits is 2240, while the sum is 25.

The square root of 221275420 is about 14875.3292400538. The cubic root of 221275420 is about 604.8454127726.

The spelling of 221275420 in words is "two hundred twenty-one million, two hundred seventy-five thousand, four hundred twenty".