222021997 has 2 divisors, whose sum is σ = 222021998. Its totient is φ = 222021996.

The previous prime is 222021983. The next prime is 222022001. The reversal of 222021997 is 799120222.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 151142436 + 70879561 = 12294^2 + 8419^2 .

It is a cyclic number.

It is not a de Polignac number, because 222021997 - 2⁷ = 222021869 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (222021977) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 111010998 + 111010999.

It is an arithmetic number, because the mean of its divisors is an integer number (111010999).

Almost surely, 2^222021997 is an apocalyptic number.

It is an amenable number.

222021997 is a deficient number, since it is larger than the sum of its proper divisors (1).

222021997 is an equidigital number, since it uses as much as digits as its factorization.

222021997 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 9072, while the sum is 34.

The square root of 222021997 is about 14900.4025784540. The cubic root of 222021997 is about 605.5248929263.

The spelling of 222021997 in words is "two hundred twenty-two million, twenty-one thousand, nine hundred ninety-seven".