21426246 has 12 divisors (see below), whose sum is σ = 46423572. Its totient is φ = 7142076.

The previous prime is 21426221. The next prime is 21426247. The reversal of 21426246 is 64262412.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21426247) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 595156 + ... + 595191.

It is an arithmetic number, because the mean of its divisors is an integer number (3868631).

Almost surely, 2^21426246 is an apocalyptic number.

21426246 is an abundant number, since it is smaller than the sum of its proper divisors (24997326).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21426246 is a wasteful number, since it uses less digits than its factorization.

21426246 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1190355 (or 1190352 counting only the distinct ones).

The product of its digits is 4608, while the sum is 27.

The square root of 21426246 is about 4628.8493170549. The cubic root of 21426246 is about 277.7465643979.

Adding to 21426246 its reverse (64262412), we get a palindrome (85688658).

The spelling of 21426246 in words is "twenty-one million, four hundred twenty-six thousand, two hundred forty-six".