22778649 has 6 divisors (see below), whose sum is σ = 32902506. Its totient is φ = 15185760.

The previous prime is 22778647. The next prime is 22778677. The reversal of 22778649 is 94687722.

It can be written as a sum of positive squares in only one way, i.e., 20115225 + 2663424 = 4485^2 + 1632^2 .

It is not a de Polignac number, because 22778649 - 2¹ = 22778647 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (22778647) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1265472 + ... + 1265489.

It is an arithmetic number, because the mean of its divisors is an integer number (5483751).

Almost surely, 2^22778649 is an apocalyptic number.

It is an amenable number.

22778649 is a deficient number, since it is larger than the sum of its proper divisors (10123857).

22778649 is a wasteful number, since it uses less digits than its factorization.

22778649 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2530967 (or 2530964 counting only the distinct ones).

The product of its digits is 338688, while the sum is 45.

The square root of 22778649 is about 4772.6982934185. The cubic root of 22778649 is about 283.4714471584.

The spelling of 22778649 in words is "twenty-two million, seven hundred seventy-eight thousand, six hundred forty-nine".