21144339 has 6 divisors (see below), whose sum is σ = 30541836. Its totient is φ = 14096220.

The previous prime is 21144323. The next prime is 21144341. The reversal of 21144339 is 93344112.

21144339 is a `hidden beast` number, since 211 + 443 + 3 + 9 = 666.

It is not a de Polignac number, because 21144339 - 2⁴ = 21144323 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21144839) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1174677 + ... + 1174694.

It is an arithmetic number, because the mean of its divisors is an integer number (5090306).

Almost surely, 2^21144339 is an apocalyptic number.

21144339 is a deficient number, since it is larger than the sum of its proper divisors (9397497).

21144339 is a wasteful number, since it uses less digits than its factorization.

21144339 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2349377 (or 2349374 counting only the distinct ones).

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

The square root of 21144339 is about 4598.2974023001. The cubic root of 21144339 is about 276.5230707554.

The spelling of 21144339 in words is "twenty-one million, one hundred forty-four thousand, three hundred thirty-nine".