21741839 has 6 divisors (see below), whose sum is σ = 25291584. Its totient is φ = 18635820.

The previous prime is 21741823. The next prime is 21741847. The reversal of 21741839 is 93814712.

It is not a de Polignac number, because 21741839 - 2⁴ = 21741823 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21741799 and 21741808.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21741869) 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, 221807 + ... + 221904.

It is an arithmetic number, because the mean of its divisors is an integer number (4215264).

Almost surely, 2^21741839 is an apocalyptic number.

21741839 is a deficient number, since it is larger than the sum of its proper divisors (3549745).

21741839 is an equidigital number, since it uses as much as digits as its factorization.

21741839 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 443725 (or 443718 counting only the distinct ones).

The product of its digits is 12096, while the sum is 35.

The square root of 21741839 is about 4662.8144934149. The cubic root of 21741839 is about 279.1035915814.

The spelling of 21741839 in words is "twenty-one million, seven hundred forty-one thousand, eight hundred thirty-nine".