22778231 has 4 divisors (see below), whose sum is σ = 26032272. Its totient is φ = 19524192.

The previous prime is 22778213. The next prime is 22778233. The reversal of 22778231 is 13287722.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-22778231 is a prime.

It is a super-2 number, since 2×22778231² = 1037695614978722, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (22778233) 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, 1627010 + ... + 1627023.

It is an arithmetic number, because the mean of its divisors is an integer number (6508068).

Almost surely, 2^22778231 is an apocalyptic number.

22778231 is a deficient number, since it is larger than the sum of its proper divisors (3254041).

22778231 is an equidigital number, since it uses as much as digits as its factorization.

22778231 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3254040.

The product of its digits is 9408, while the sum is 32.

The square root of 22778231 is about 4772.6545024755. The cubic root of 22778231 is about 283.4697131986.

The spelling of 22778231 in words is "twenty-two million, seven hundred seventy-eight thousand, two hundred thirty-one".