21142339 has 12 divisors (see below), whose sum is σ = 22913064. Its totient is φ = 19440704.

The previous prime is 21142291. The next prime is 21142343. The reversal of 21142339 is 93324112.

It is not a de Polignac number, because 21142339 - 2¹¹ = 21140291 is a prime.

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 (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 37272 + ... + 37834.

It is an arithmetic number, because the mean of its divisors is an integer number (1909422).

Almost surely, 2^21142339 is an apocalyptic number.

21142339 is a deficient number, since it is larger than the sum of its proper divisors (1770725).

21142339 is an equidigital number, since it uses as much as digits as its factorization.

21142339 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 674 (or 627 counting only the distinct ones).

The product of its digits is 1296, while the sum is 25.

The square root of 21142339 is about 4598.0799253601. The cubic root of 21142339 is about 276.5143518956.

The spelling of 21142339 in words is "twenty-one million, one hundred forty-two thousand, three hundred thirty-nine".