21941613 has 12 divisors (see below), whose sum is σ = 31798780. Its totient is φ = 14579136.

The previous prime is 21941581. The next prime is 21941651. The reversal of 21941613 is 31614912.

21941613 is a `hidden beast` number, since 2 + 1 + 9 + 41 + 613 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 4652649 + 17288964 = 2157^2 + 4158^2 .

It is not a de Polignac number, because 21941613 - 2⁵ = 21941581 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21941113) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1078 + ... + 6711.

Almost surely, 2^21941613 is an apocalyptic number.

It is an amenable number.

21941613 is a deficient number, since it is larger than the sum of its proper divisors (9857167).

21941613 is a wasteful number, since it uses less digits than its factorization.

21941613 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8108 (or 8105 counting only the distinct ones).

The product of its digits is 1296, while the sum is 27.

The square root of 21941613 is about 4684.1875496184. The cubic root of 21941613 is about 279.9558306178.

The spelling of 21941613 in words is "twenty-one million, nine hundred forty-one thousand, six hundred thirteen".