21418245 has 24 divisors (see below), whose sum is σ = 37346400. Its totient is φ = 11354976.

The previous prime is 21418237. The next prime is 21418247. The reversal of 21418245 is 54281412.

21418245 is a `hidden beast` number, since 2 + 1 + 418 + 245 = 666.

It is not a de Polignac number, because 21418245 - 2³ = 21418237 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21418247) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 6726 + ... + 9384.

It is an arithmetic number, because the mean of its divisors is an integer number (1556100).

Almost surely, 2^21418245 is an apocalyptic number.

It is an amenable number.

21418245 is a deficient number, since it is larger than the sum of its proper divisors (15928155).

21418245 is a wasteful number, since it uses less digits than its factorization.

21418245 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2849 (or 2846 counting only the distinct ones).

The product of its digits is 2560, while the sum is 27.

The square root of 21418245 is about 4627.9849826896. The cubic root of 21418245 is about 277.7119880046.

Adding to 21418245 its reverse (54281412), we get a palindrome (75699657).

The spelling of 21418245 in words is "twenty-one million, four hundred eighteen thousand, two hundred forty-five".