21846920 has 16 divisors (see below), whose sum is σ = 49155660. Its totient is φ = 8738752.

The previous prime is 21846911. The next prime is 21846931. The reversal of 21846920 is 2964812.

It can be written as a sum of positive squares in 2 ways, for example, as 20921476 + 925444 = 4574^2 + 962^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 273047 + ... + 273126.

Almost surely, 2^21846920 is an apocalyptic number.

21846920 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21846920 is an abundant number, since it is smaller than the sum of its proper divisors (27308740).

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

21846920 is a wasteful number, since it uses less digits than its factorization.

21846920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 546184 (or 546180 counting only the distinct ones).

The product of its (nonzero) digits is 6912, while the sum is 32.

The square root of 21846920 is about 4674.0688912338. The cubic root of 21846920 is about 279.5525165254.

The spelling of 21846920 in words is "twenty-one million, eight hundred forty-six thousand, nine hundred twenty".