21054473 has 4 divisors (see below), whose sum is σ = 22968528. Its totient is φ = 19140420.

The previous prime is 21054457. The next prime is 21054521. The reversal of 21054473 is 37445012.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 21054473 - 2⁴ = 21054457 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21054403) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 957011 + ... + 957032.

It is an arithmetic number, because the mean of its divisors is an integer number (5742132).

Almost surely, 2^21054473 is an apocalyptic number.

It is an amenable number.

21054473 is a deficient number, since it is larger than the sum of its proper divisors (1914055).

21054473 is a wasteful number, since it uses less digits than its factorization.

21054473 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1914054.

The product of its (nonzero) digits is 3360, while the sum is 26.

The square root of 21054473 is about 4588.5153372306. The cubic root of 21054473 is about 276.1307622698.

Adding to 21054473 its reverse (37445012), we get a palindrome (58499485).

The spelling of 21054473 in words is "twenty-one million, fifty-four thousand, four hundred seventy-three".