21183380 has 12 divisors (see below), whose sum is σ = 44485140. Its totient is φ = 8473344.

The previous prime is 21183373. The next prime is 21183389. The reversal of 21183380 is 8338112.

It can be written as a sum of positive squares in 2 ways, for example, as 14485636 + 6697744 = 3806^2 + 2588^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21183389) 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, 529565 + ... + 529604.

It is an arithmetic number, because the mean of its divisors is an integer number (3707095).

Almost surely, 2^21183380 is an apocalyptic number.

21183380 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21183380 is an abundant number, since it is smaller than the sum of its proper divisors (23301760).

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

21183380 is a wasteful number, since it uses less digits than its factorization.

21183380 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1059178 (or 1059176 counting only the distinct ones).

The product of its (nonzero) digits is 1152, while the sum is 26.

The square root of 21183380 is about 4602.5406027541. The cubic root of 21183380 is about 276.6931572512.

The spelling of 21183380 in words is "twenty-one million, one hundred eighty-three thousand, three hundred eighty".