22218651 has 32 divisors (see below), whose sum is σ = 40517120. Its totient is φ = 11718432.

The previous prime is 22218649. The next prime is 22218683. The reversal of 22218651 is 15681222.

It is a happy number.

22218651 is a `hidden beast` number, since 2 + 2 + 2 + 1 + 8 + 651 = 666.

It is not a de Polignac number, because 22218651 - 2¹ = 22218649 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is not an unprimeable number, because it can be changed into a prime (22218601) 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 31 ways as a sum of consecutive naturals, for example, 2065 + ... + 6978.

It is an arithmetic number, because the mean of its divisors is an integer number (1266160).

Almost surely, 2^22218651 is an apocalyptic number.

22218651 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

22218651 is a deficient number, since it is larger than the sum of its proper divisors (18298469).

22218651 is a wasteful number, since it uses less digits than its factorization.

22218651 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9072 (or 9066 counting only the distinct ones).

The product of its digits is 1920, while the sum is 27.

The square root of 22218651 is about 4713.6664073734. Note that the first 3 decimals coincide. The cubic root of 22218651 is about 281.1291605330.

Adding to 22218651 its reverse (15681222), we get a palindrome (37899873).

The spelling of 22218651 in words is "twenty-two million, two hundred eighteen thousand, six hundred fifty-one".