21918034 has 8 divisors (see below), whose sum is σ = 34306560. Its totient is φ = 10482516.

The previous prime is 21918019. The next prime is 21918037. The reversal of 21918034 is 43081912.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a junction number, because it is equal to n+sod(n) for n = 21917993 and 21918011.

It is not an unprimeable number, because it can be changed into a prime (21918037) 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, 238194 + ... + 238285.

It is an arithmetic number, because the mean of its divisors is an integer number (4288320).

Almost surely, 2^21918034 is an apocalyptic number.

21918034 is a deficient number, since it is larger than the sum of its proper divisors (12388526).

21918034 is a wasteful number, since it uses less digits than its factorization.

21918034 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 476504.

The product of its (nonzero) digits is 1728, while the sum is 28.

The square root of 21918034 is about 4681.6700011855. The cubic root of 21918034 is about 279.8555121878.

Adding to 21918034 its reverse (43081912), we get a palindrome (64999946).

The spelling of 21918034 in words is "twenty-one million, nine hundred eighteen thousand, thirty-four".