21470481 has 8 divisors (see below), whose sum is σ = 31808160. Its totient is φ = 14313636.

The previous prime is 21470467. The next prime is 21470483. The reversal of 21470481 is 18407412.

It is not a de Polignac number, because 21470481 - 2⁶ = 21470417 is a prime.

It is a super-2 number, since 2×21470481² = 921963108742722, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (27), and also a Moran number because the ratio is a prime number: 795203 = 21470481 / (2 + 1 + 4 + 7 + 0 + 4 + 8 + 1).

It is not an unprimeable number, because it can be changed into a prime (21470483) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 397575 + ... + 397628.

It is an arithmetic number, because the mean of its divisors is an integer number (3976020).

Almost surely, 2^21470481 is an apocalyptic number.

It is an amenable number.

21470481 is a deficient number, since it is larger than the sum of its proper divisors (10337679).

21470481 is an equidigital number, since it uses as much as digits as its factorization.

21470481 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 795212 (or 795206 counting only the distinct ones).

The product of its (nonzero) digits is 1792, while the sum is 27.

The square root of 21470481 is about 4633.6250387790. The cubic root of 21470481 is about 277.9375711654.

Adding to 21470481 its reverse (18407412), we get a palindrome (39877893).

The spelling of 21470481 in words is "twenty-one million, four hundred seventy thousand, four hundred eighty-one".