21020846 has 24 divisors (see below), whose sum is σ = 39612720. Its totient is φ = 8189280.

The previous prime is 21020843. The next prime is 21020849. The reversal of 21020846 is 64802012.

It is an interprime number because it is at equal distance from previous prime (21020843) and next prime (21020849).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21020843) 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, 4511 + ... + 7898.

It is an arithmetic number, because the mean of its divisors is an integer number (1650530).

Almost surely, 2^21020846 is an apocalyptic number.

21020846 is a deficient number, since it is larger than the sum of its proper divisors (18591874).

21020846 is a wasteful number, since it uses less digits than its factorization.

21020846 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12440 (or 12429 counting only the distinct ones).

The product of its (nonzero) digits is 768, while the sum is 23.

The square root of 21020846 is about 4584.8496158544. The cubic root of 21020846 is about 275.9836771835.

Adding to 21020846 its reverse (64802012), we get a palindrome (85822858).

The spelling of 21020846 in words is "twenty-one million, twenty thousand, eight hundred forty-six".