220221210991 has 2 divisors, whose sum is σ = 220221210992. Its totient is φ = 220221210990.

The previous prime is 220221210967. The next prime is 220221211037. The reversal of 220221210991 is 199012122022.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 220221210991 - 2⁷ = 220221210863 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (220221210901) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 110110605495 + 110110605496.

It is an arithmetic number, because the mean of its divisors is an integer number (110110605496).

Almost surely, 2^220221210991 is an apocalyptic number.

220221210991 is a deficient number, since it is larger than the sum of its proper divisors (1).

220221210991 is an equidigital number, since it uses as much as digits as its factorization.

220221210991 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2592, while the sum is 31.

The spelling of 220221210991 in words is "two hundred twenty billion, two hundred twenty-one million, two hundred ten thousand, nine hundred ninety-one".