21474553 has 4 divisors (see below), whose sum is σ = 22737780. Its totient is φ = 20211328.

The previous prime is 21474533. The next prime is 21474559. The reversal of 21474553 is 35547412.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 15776784 + 5697769 = 3972^2 + 2387^2 .

It is a cyclic number.

It is not a de Polignac number, because 21474553 - 2⁵ = 21474521 is a prime.

It is a super-2 number, since 2×21474553² = 922312853099618, which contains 22 as substring.

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21474559) 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, 631588 + ... + 631621.

It is an arithmetic number, because the mean of its divisors is an integer number (5684445).

Almost surely, 2^21474553 is an apocalyptic number.

It is an amenable number.

21474553 is a deficient number, since it is larger than the sum of its proper divisors (1263227).

21474553 is a wasteful number, since it uses less digits than its factorization.

21474553 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1263226.

The product of its digits is 16800, while the sum is 31.

The square root of 21474553 is about 4634.0644147444. The cubic root of 21474553 is about 277.9551408735.

The spelling of 21474553 in words is "twenty-one million, four hundred seventy-four thousand, five hundred fifty-three".