22781993 has 8 divisors (see below), whose sum is σ = 25326336. Its totient is φ = 20350800.

The previous prime is 22781987. The next prime is 22782017. The reversal of 22781993 is 39918722.

It is a happy number.

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 22781993 - 2⁴ = 22781977 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 22781993.

It is not an unprimeable number, because it can be changed into a prime (22781933) 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 7 ways as a sum of consecutive naturals, for example, 27863 + ... + 28668.

It is an arithmetic number, because the mean of its divisors is an integer number (3165792).

Almost surely, 2^22781993 is an apocalyptic number.

It is an amenable number.

22781993 is a deficient number, since it is larger than the sum of its proper divisors (2544343).

22781993 is a wasteful number, since it uses less digits than its factorization.

22781993 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 56575.

The product of its digits is 54432, while the sum is 41.

The square root of 22781993 is about 4773.0486064988. The cubic root of 22781993 is about 283.4853180738.

The spelling of 22781993 in words is "twenty-two million, seven hundred eighty-one thousand, nine hundred ninety-three".