22440257 has 4 divisors (see below), whose sum is σ = 25646016. Its totient is φ = 19234500.

The previous prime is 22440251. The next prime is 22440259. The reversal of 22440257 is 75204422.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 75204422 = 2 ⋅37602211.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-22440257 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (22440251) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1602869 + ... + 1602882.

It is an arithmetic number, because the mean of its divisors is an integer number (6411504).

Almost surely, 2^22440257 is an apocalyptic number.

It is an amenable number.

22440257 is a deficient number, since it is larger than the sum of its proper divisors (3205759).

22440257 is an equidigital number, since it uses as much as digits as its factorization.

22440257 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3205758.

The product of its (nonzero) digits is 4480, while the sum is 26.

The square root of 22440257 is about 4737.1148392244. The cubic root of 22440257 is about 282.0607191151.

Adding to 22440257 its reverse (75204422), we get a palindrome (97644679).

The spelling of 22440257 in words is "twenty-two million, four hundred forty thousand, two hundred fifty-seven".