21318194 has 16 divisors (see below), whose sum is σ = 33870528. Its totient is φ = 10042032.

The previous prime is 21318191. The next prime is 21318203. The reversal of 21318194 is 49181312.

It is not an unprimeable number, because it can be changed into a prime (21318191) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 377 + ... + 6540.

It is an arithmetic number, because the mean of its divisors is an integer number (2116908).

Almost surely, 2^21318194 is an apocalyptic number.

21318194 is a deficient number, since it is larger than the sum of its proper divisors (12552334).

21318194 is a wasteful number, since it uses less digits than its factorization.

21318194 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7009.

The product of its digits is 1728, while the sum is 29.

The square root of 21318194 is about 4617.1629817454. The cubic root of 21318194 is about 277.2788877932.

It can be divided in two parts, 21318 and 194, that added together give a palindrome (21512).

The spelling of 21318194 in words is "twenty-one million, three hundred eighteen thousand, one hundred ninety-four".