220021000 has 32 divisors (see below), whose sum is σ = 514851480. Its totient is φ = 88008000.

The previous prime is 220020949. The next prime is 220021003. The reversal of 220021000 is 120022.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 95609284 + 124411716 = 9778^2 + 11154^2 .

It is not an unprimeable number, because it can be changed into a prime (220021003) 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, 109011 + ... + 111010.

Almost surely, 2^220021000 is an apocalyptic number.

220021000 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

220021000 is an abundant number, since it is smaller than the sum of its proper divisors (294830480).

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

220021000 is a wasteful number, since it uses less digits than its factorization.

220021000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 220042 (or 220028 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 7.

The square root of 220021000 is about 14833.1048671544. The cubic root of 220021000 is about 603.7002811028.

Adding to 220021000 its reverse (120022), we get a palindrome (220141022).

The spelling of 220021000 in words is "two hundred twenty million, twenty-one thousand".