22378221 has 8 divisors (see below), whose sum is σ = 33152960. Its totient is φ = 14918796.

The previous prime is 22378217. The next prime is 22378231. The reversal of 22378221 is 12287322.

It is a happy number.

It is not a de Polignac number, because 22378221 - 2² = 22378217 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27), and also a Moran number because the ratio is a prime number: 828823 = 22378221 / (2 + 2 + 3 + 7 + 8 + 2 + 2 + 1).

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (22378231) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 414385 + ... + 414438.

It is an arithmetic number, because the mean of its divisors is an integer number (4144120).

Almost surely, 2^22378221 is an apocalyptic number.

It is an amenable number.

22378221 is a deficient number, since it is larger than the sum of its proper divisors (10774739).

22378221 is an equidigital number, since it uses as much as digits as its factorization.

22378221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 828832 (or 828826 counting only the distinct ones).

The product of its digits is 2688, while the sum is 27.

The square root of 22378221 is about 4730.5624401333. The cubic root of 22378221 is about 281.8005606584.

The spelling of 22378221 in words is "twenty-two million, three hundred seventy-eight thousand, two hundred twenty-one".