221122021 has 4 divisors (see below), whose sum is σ = 221156992. Its totient is φ = 221087052.

The previous prime is 221122003. The next prime is 221122049. The reversal of 221122021 is 120221122.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-221122021 is a prime.

It is a super-2 number, since 2×221122021² = 97789896342248882, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 221121992 and 221122010.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221122091) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5055 + ... + 21628.

It is an arithmetic number, because the mean of its divisors is an integer number (55289248).

Almost surely, 2^221122021 is an apocalyptic number.

It is an amenable number.

221122021 is a deficient number, since it is larger than the sum of its proper divisors (34971).

221122021 is an equidigital number, since it uses as much as digits as its factorization.

221122021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 34970.

The product of its (nonzero) digits is 32, while the sum is 13.

The square root of 221122021 is about 14870.1721913366. The cubic root of 221122021 is about 604.7056109361.

Adding to 221122021 its reverse (120221122), we get a palindrome (341343143).

The spelling of 221122021 in words is "two hundred twenty-one million, one hundred twenty-two thousand, twenty-one".