21200549 has 8 divisors (see below), whose sum is σ = 22239360. Its totient is φ = 20171536.

The previous prime is 21200539. The next prime is 21200563. The reversal of 21200549 is 94500212.

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

It is a cyclic number.

It is not a de Polignac number, because 21200549 - 2⁴ = 21200533 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (23).

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21200539) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2192 + ... + 6870.

It is an arithmetic number, because the mean of its divisors is an integer number (2779920).

Almost surely, 2^21200549 is an apocalyptic number.

It is an amenable number.

21200549 is a deficient number, since it is larger than the sum of its proper divisors (1038811).

21200549 is a wasteful number, since it uses less digits than its factorization.

21200549 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4899.

The product of its (nonzero) digits is 720, while the sum is 23.

The square root of 21200549 is about 4604.4053904929. The cubic root of 21200549 is about 276.7678897690.

The spelling of 21200549 in words is "twenty-one million, two hundred thousand, five hundred forty-nine".