22278281 has 8 divisors (see below), whose sum is σ = 22625064. Its totient is φ = 21934080.

The previous prime is 22278247. The next prime is 22278287. The reversal of 22278281 is 18287222.

It can be written as a sum of positive squares in 4 ways, for example, as 4343056 + 17935225 = 2084^2 + 4235^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 22278281 - 2¹⁰ = 22277257 is a prime.

It is a super-2 number, since 2×22278281² = 992643608629922, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (22278287) 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, 22901 + ... + 23853.

It is an arithmetic number, because the mean of its divisors is an integer number (2828133).

Almost surely, 2^22278281 is an apocalyptic number.

It is an amenable number.

22278281 is a deficient number, since it is larger than the sum of its proper divisors (346783).

22278281 is an equidigital number, since it uses as much as digits as its factorization.

22278281 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1291.

The product of its digits is 7168, while the sum is 32.

The square root of 22278281 is about 4719.9873940510. The cubic root of 22278281 is about 281.3804322751.

The spelling of 22278281 in words is "twenty-two million, two hundred seventy-eight thousand, two hundred eighty-one".