21946541 has 8 divisors (see below), whose sum is σ = 23478840. Its totient is φ = 20441088.

The previous prime is 21946517. The next prime is 21946549. The reversal of 21946541 is 14564912.

It can be written as a sum of positive squares in 4 ways, for example, as 592900 + 21353641 = 770^2 + 4621^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21946541 - 2¹⁴ = 21930157 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21946498 and 21946507.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21946549) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5006 + ... + 8303.

It is an arithmetic number, because the mean of its divisors is an integer number (2934855).

Almost surely, 2^21946541 is an apocalyptic number.

It is an amenable number.

21946541 is a deficient number, since it is larger than the sum of its proper divisors (1532299).

21946541 is a wasteful number, since it uses less digits than its factorization.

21946541 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13423.

The product of its digits is 8640, while the sum is 32.

The square root of 21946541 is about 4684.7135451381. The cubic root of 21946541 is about 279.9767880418.

The spelling of 21946541 in words is "twenty-one million, nine hundred forty-six thousand, five hundred forty-one".