221427660 has 48 divisors (see below), whose sum is σ = 620831232. Its totient is φ = 58968000.

The previous prime is 221427659. The next prime is 221427671. The reversal of 221427660 is 66724122.

It is a super-2 number, since 2×221427660² = 98060417226151200, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 52635 + ... + 56685.

It is an arithmetic number, because the mean of its divisors is an integer number (12933984).

Almost surely, 2^221427660 is an apocalyptic number.

221427660 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

221427660 is an abundant number, since it is smaller than the sum of its proper divisors (399403572).

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

221427660 is a wasteful number, since it uses less digits than its factorization.

221427660 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4974 (or 4972 counting only the distinct ones).

The product of its (nonzero) digits is 8064, while the sum is 30.

The square root of 221427660 is about 14880.4455578454. The cubic root of 221427660 is about 604.9840944752.

The spelling of 221427660 in words is "two hundred twenty-one million, four hundred twenty-seven thousand, six hundred sixty".