21044473 has 2 divisors, whose sum is σ = 21044474.
Its totient is φ = 21044472.
The previous prime is 21044467. The next prime is 21044477. The reversal of 21044473 is 37444012.
Adding to 21044473 its reverse (37444012), we get a palindrome (58488485).
It is a strong prime.
It can be written as a sum of positive squares in only one way, i.e., 19333609 + 1710864 = 4397^2 + 1308^2
It is a cyclic number.
It is not a de Polignac number, because 21044473 - 217 = 20913401 is a prime.
It is not a weakly prime, because it can be changed into another prime (21044477) by changing a digit.
It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10522236 + 10522237.
It is an arithmetic number, because the mean of its divisors is an integer number (10522237).
Almost surely, 221044473 is an apocalyptic number.
It is an amenable number.
21044473 is a deficient number, since it is larger than the sum of its proper divisors (1).
21044473 is an equidigital number, since it uses as much as digits as its factorization.
21044473 is an evil number, because the sum of its binary digits is even.
The product of its (nonzero) digits is 2688, while the sum is 25.
The square root of 21044473 is about 4587.4255307307.
The cubic root of 21044473 is about 276.0870384665.
The spelling of 21044473 in words is "twenty-one million, forty-four thousand, four hundred seventy-three".