21366612 has 48 divisors (see below), whose sum is σ = 56902720. Its totient is φ = 6928416.

The previous prime is 21366593. The next prime is 21366619. The reversal of 21366612 is 21666312.

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

It is a nude number because it is divisible by every one of its digits.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21366619) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1323 + ... + 6669.

Almost surely, 2^21366612 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21366612, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (28451360).

21366612 is an abundant number, since it is smaller than the sum of its proper divisors (35536108).

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

21366612 is a wasteful number, since it uses less digits than its factorization.

21366612 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5397 (or 5389 counting only the distinct ones).

The product of its digits is 2592, while the sum is 27.

The square root of 21366612 is about 4622.4032710269. The cubic root of 21366612 is about 277.4886481843.

The spelling of 21366612 in words is "twenty-one million, three hundred sixty-six thousand, six hundred twelve".