22399145 has 4 divisors (see below), whose sum is σ = 26878980. Its totient is φ = 17919312.

The previous prime is 22399141. The next prime is 22399147. The reversal of 22399145 is 54199322.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 54199322 = 2 ⋅27099661.

It can be written as a sum of positive squares in 2 ways, for example, as 9467929 + 12931216 = 3077^2 + 3596^2 .

It is a cyclic number.

It is not a de Polignac number, because 22399145 - 2² = 22399141 is a prime.

It is not an unprimeable number, because it can be changed into a prime (22399141) 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, 2239910 + ... + 2239919.

It is an arithmetic number, because the mean of its divisors is an integer number (6719745).

Almost surely, 2^22399145 is an apocalyptic number.

It is an amenable number.

22399145 is a deficient number, since it is larger than the sum of its proper divisors (4479835).

22399145 is an equidigital number, since it uses as much as digits as its factorization.

22399145 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4479834.

The product of its digits is 19440, while the sum is 35.

The square root of 22399145 is about 4732.7734997568. The cubic root of 22399145 is about 281.8883626653. Note that the first 3 decimals are identical.

The spelling of 22399145 in words is "twenty-two million, three hundred ninety-nine thousand, one hundred forty-five".