21494718 has 48 divisors (see below), whose sum is σ = 54951936. Its totient is φ = 5942160.

The previous prime is 21494717. The next prime is 21494723. The reversal of 21494718 is 81749412.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21494717) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1155 + ... + 6657.

It is an arithmetic number, because the mean of its divisors is an integer number (1144832).

Almost surely, 2^21494718 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21494718, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27475968).

21494718 is an abundant number, since it is smaller than the sum of its proper divisors (33457218).

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

21494718 is a wasteful number, since it uses less digits than its factorization.

21494718 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5549 (or 5546 counting only the distinct ones).

The product of its digits is 16128, while the sum is 36.

The square root of 21494718 is about 4636.2396400531. The cubic root of 21494718 is about 278.0421153178.

The spelling of 21494718 in words is "twenty-one million, four hundred ninety-four thousand, seven hundred eighteen".