21199408 has 40 divisors (see below), whose sum is σ = 44260560. Its totient is φ = 9799680.

The previous prime is 21199369. The next prime is 21199411. The reversal of 21199408 is 80499112.

It is a Harshad number since it is a multiple of its sum of digits (34).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 15388 + ... + 16708.

It is an arithmetic number, because the mean of its divisors is an integer number (1106514).

Almost surely, 2^21199408 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 21199408, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (22130280).

21199408 is an abundant number, since it is smaller than the sum of its proper divisors (23061152).

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

21199408 is a wasteful number, since it uses less digits than its factorization.

21199408 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1405 (or 1399 counting only the distinct ones).

The product of its (nonzero) digits is 5184, while the sum is 34.

The square root of 21199408 is about 4604.2814857478. The cubic root of 21199408 is about 276.7629245229.

The spelling of 21199408 in words is "twenty-one million, one hundred ninety-nine thousand, four hundred eight".