21143349 has 20 divisors (see below), whose sum is σ = 32677260. Its totient is φ = 13608000.

The previous prime is 21143327. The next prime is 21143357. The reversal of 21143349 is 94334112.

It can be written as a sum of positive squares in 2 ways, for example, as 7193124 + 13950225 = 2682^2 + 3735^2 .

It is not a de Polignac number, because 21143349 - 2¹² = 21139253 is a prime.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21142349) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 2152 + ... + 6849.

It is an arithmetic number, because the mean of its divisors is an integer number (1633863).

Almost surely, 2^21143349 is an apocalyptic number.

21143349 is a gapful number since it is divisible by the number (29) formed by its first and last digit.

It is an amenable number.

21143349 is a deficient number, since it is larger than the sum of its proper divisors (11533911).

21143349 is an equidigital number, since it uses as much as digits as its factorization.

21143349 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9042 (or 9033 counting only the distinct ones).

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

The square root of 21143349 is about 4598.1897525004. The cubic root of 21143349 is about 276.5187549885.

The spelling of 21143349 in words is "twenty-one million, one hundred forty-three thousand, three hundred forty-nine".