220231021 has 2 divisors, whose sum is σ = 220231022. Its totient is φ = 220231020.

The previous prime is 220231007. The next prime is 220231027. The reversal of 220231021 is 120132022.

220231021 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 217238121 + 2992900 = 14739^2 + 1730^2 .

It is a cyclic number.

It is not a de Polignac number, because 220231021 - 2⁹ = 220230509 is a prime.

It is a super-2 number, since 2×220231021² = 97003405221404882, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 220230992 and 220231010.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (220231027) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 110115510 + 110115511.

It is an arithmetic number, because the mean of its divisors is an integer number (110115511).

Almost surely, 2^220231021 is an apocalyptic number.

It is an amenable number.

220231021 is a deficient number, since it is larger than the sum of its proper divisors (1).

220231021 is an equidigital number, since it uses as much as digits as its factorization.

220231021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 48, while the sum is 13.

The square root of 220231021 is about 14840.1826471240. The cubic root of 220231021 is about 603.8923073423.

Adding to 220231021 its reverse (120132022), we get a palindrome (340363043).

The spelling of 220231021 in words is "two hundred twenty million, two hundred thirty-one thousand, twenty-one".