21774318 has 8 divisors (see below), whose sum is σ = 43548648. Its totient is φ = 7258104.

The previous prime is 21774317. The next prime is 21774329. The reversal of 21774318 is 81347712.

It is a happy number.

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

21774318 is an admirable number.

It is a Smith number, since the sum of its digits (33) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21774317) 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, 1814521 + ... + 1814532.

It is an arithmetic number, because the mean of its divisors is an integer number (5443581).

Almost surely, 2^21774318 is an apocalyptic number.

21774318 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21774318 is a wasteful number, since it uses less digits than its factorization.

21774318 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3629058.

The product of its digits is 9408, while the sum is 33.

The square root of 21774318 is about 4666.2959614667. The cubic root of 21774318 is about 279.2425018698.

The spelling of 21774318 in words is "twenty-one million, seven hundred seventy-four thousand, three hundred eighteen".