122218391 has 4 divisors (see below), whose sum is σ = 123097800. Its totient is φ = 121338984.

The previous prime is 122218387. The next prime is 122218403. The reversal of 122218391 is 193812221.

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

It is a cyclic number.

It is not a de Polignac number, because 122218391 - 2² = 122218387 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 (122218381) 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, 439496 + ... + 439773.

It is an arithmetic number, because the mean of its divisors is an integer number (30774450).

Almost surely, 2^122218391 is an apocalyptic number.

122218391 is a deficient number, since it is larger than the sum of its proper divisors (879409).

122218391 is an equidigital number, since it uses as much as digits as its factorization.

122218391 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 879408.

The product of its digits is 1728, while the sum is 29.

The square root of 122218391 is about 11055.2426929489. The cubic root of 122218391 is about 496.2633321926.

The spelling of 122218391 in words is "one hundred twenty-two million, two hundred eighteen thousand, three hundred ninety-one".