21389141 has 2 divisors, whose sum is σ = 21389142. Its totient is φ = 21389140.

The previous prime is 21389119. The next prime is 21389161. The reversal of 21389141 is 14198312.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 20295025 + 1094116 = 4505^2 + 1046^2 .

It is a cyclic number.

It is not a de Polignac number, because 21389141 - 2¹⁰ = 21388117 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21389161) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10694570 + 10694571.

It is an arithmetic number, because the mean of its divisors is an integer number (10694571).

Almost surely, 2^21389141 is an apocalyptic number.

It is an amenable number.

21389141 is a deficient number, since it is larger than the sum of its proper divisors (1).

21389141 is an equidigital number, since it uses as much as digits as its factorization.

21389141 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1728, while the sum is 29.

The square root of 21389141 is about 4624.8395647849. The cubic root of 21389141 is about 277.5861421284.

The spelling of 21389141 in words is "twenty-one million, three hundred eighty-nine thousand, one hundred forty-one".