21946245 has 16 divisors (see below), whose sum is σ = 35341440. Its totient is φ = 11628864.

The previous prime is 21946241. The next prime is 21946247. The reversal of 21946245 is 54264912.

It is not a de Polignac number, because 21946245 - 2² = 21946241 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21946241) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2305 + ... + 7014.

It is an arithmetic number, because the mean of its divisors is an integer number (2208840).

Almost surely, 2^21946245 is an apocalyptic number.

It is an amenable number.

21946245 is a deficient number, since it is larger than the sum of its proper divisors (13395195).

21946245 is a wasteful number, since it uses less digits than its factorization.

21946245 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9484.

The product of its digits is 17280, while the sum is 33.

The square root of 21946245 is about 4684.6819529185. The cubic root of 21946245 is about 279.9755293240.

It can be divided in two parts, 219 and 46245, that added together give a palindrome (46464).

The spelling of 21946245 in words is "twenty-one million, nine hundred forty-six thousand, two hundred forty-five".