21470563 has 2 divisors, whose sum is σ = 21470564. Its totient is φ = 21470562.

The previous prime is 21470557. The next prime is 21470567. The reversal of 21470563 is 36507412.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21470563 - 2²¹ = 19373411 is a prime.

It is an alternating number because its digits alternate between even and odd.

It is not a weakly prime, because it can be changed into another prime (21470567) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10735281 + 10735282.

It is an arithmetic number, because the mean of its divisors is an integer number (10735282).

Almost surely, 2^21470563 is an apocalyptic number.

21470563 is a deficient number, since it is larger than the sum of its proper divisors (1).

21470563 is an equidigital number, since it uses as much as digits as its factorization.

21470563 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 5040, while the sum is 28.

The square root of 21470563 is about 4633.6338871344. The cubic root of 21470563 is about 277.9379249978.

Adding to 21470563 its reverse (36507412), we get a palindrome (57977975).

The spelling of 21470563 in words is "twenty-one million, four hundred seventy thousand, five hundred sixty-three".