21472844 has 12 divisors (see below), whose sum is σ = 38286864. Its totient is φ = 10533744.

The previous prime is 21472817. The next prime is 21472849. The reversal of 21472844 is 44827412.

It is a super-2 number, since 2×21472844² = 922166058896672, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 21472844.

It is not an unprimeable number, because it can be changed into a prime (21472849) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 50432 + ... + 50855.

It is an arithmetic number, because the mean of its divisors is an integer number (3190572).

Almost surely, 2^21472844 is an apocalyptic number.

It is an amenable number.

21472844 is a deficient number, since it is larger than the sum of its proper divisors (16814020).

21472844 is a wasteful number, since it uses less digits than its factorization.

21472844 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 101344 (or 101342 counting only the distinct ones).

The product of its digits is 14336, while the sum is 32.

The square root of 21472844 is about 4633.8800157104. The cubic root of 21472844 is about 277.9477672169.

The spelling of 21472844 in words is "twenty-one million, four hundred seventy-two thousand, eight hundred forty-four".