21845208 has 64 divisors (see below), whose sum is σ = 68094720. Its totient is φ = 5673600.

The previous prime is 21845203. The next prime is 21845233. The reversal of 21845208 is 80254812.

It is a super-2 number, since 2×21845208² = 954426225126528, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21845203) 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, 4063 + ... + 7758.

It is an arithmetic number, because the mean of its divisors is an integer number (1063980).

Almost surely, 2^21845208 is an apocalyptic number.

21845208 is a gapful number since it is divisible by the number (28) formed by its first and last digit.

It is an amenable number.

21845208 is an abundant number, since it is smaller than the sum of its proper divisors (46249512).

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

21845208 is a wasteful number, since it uses less digits than its factorization.

21845208 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11848 (or 11844 counting only the distinct ones).

The product of its (nonzero) digits is 5120, while the sum is 30.

The square root of 21845208 is about 4673.8857495664. The cubic root of 21845208 is about 279.5452141015.

The spelling of 21845208 in words is "twenty-one million, eight hundred forty-five thousand, two hundred eight".