222121397 has 4 divisors (see below), whose sum is σ = 228124716. Its totient is φ = 216118080.

The previous prime is 222121379. The next prime is 222121423. The reversal of 222121397 is 793121222.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 148693636 + 73427761 = 12194^2 + 8569^2 .

It is a cyclic number.

It is not a de Polignac number, because 222121397 - 2¹⁰ = 222120373 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (222121307) 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 in 3 ways as a sum of consecutive naturals, for example, 3001604 + ... + 3001677.

It is an arithmetic number, because the mean of its divisors is an integer number (57031179).

Almost surely, 2^222121397 is an apocalyptic number.

It is an amenable number.

222121397 is a deficient number, since it is larger than the sum of its proper divisors (6003319).

222121397 is an equidigital number, since it uses as much as digits as its factorization.

222121397 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6003318.

The product of its digits is 3024, while the sum is 29.

The square root of 222121397 is about 14903.7376855606. The cubic root of 222121397 is about 605.6152446258.

It can be divided in two parts, 2221213 and 97, that multiplied together give a triangular number (215457661 = T₂₀₇₅₈).

The spelling of 222121397 in words is "two hundred twenty-two million, one hundred twenty-one thousand, three hundred ninety-seven".