221040100 has 18 divisors (see below), whose sum is σ = 479657234. Its totient is φ = 88416000.

The previous prime is 221040089. The next prime is 221040101. The reversal of 221040100 is 1040122.

It can be written as a sum of positive squares in 3 ways, for example, as 26604964 + 194435136 = 5158^2 + 13944^2 .

It is a super-3 number, since 3×221040100³ (a number of 26 digits) contains 333 as substring.

It is a Harshad number since it is a multiple of its sum of digits (10).

It is not an unprimeable number, because it can be changed into a prime (221040101) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1105101 + ... + 1105300.

Almost surely, 2^221040100 is an apocalyptic number.

221040100 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

221040100 is an abundant number, since it is smaller than the sum of its proper divisors (258617134).

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

221040100 is a wasteful number, since it uses less digits than its factorization.

221040100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2210415 (or 2210408 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 10.

The square root of 221040100 is about 14867.4173950959. The cubic root of 221040100 is about 604.6309248616.

Adding to 221040100 its reverse (1040122), we get a palindrome (222080222).

The spelling of 221040100 in words is "two hundred twenty-one million, forty thousand, one hundred".