21460247 has 16 divisors (see below), whose sum is σ = 22809600. Its totient is φ = 20170080.

The previous prime is 21460237. The next prime is 21460331. The reversal of 21460247 is 74206412.

It is a cyclic number.

It is not a de Polignac number, because 21460247 - 2¹² = 21456151 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21460207) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 196829 + ... + 196937.

It is an arithmetic number, because the mean of its divisors is an integer number (1425600).

Almost surely, 2^21460247 is an apocalyptic number.

21460247 is a deficient number, since it is larger than the sum of its proper divisors (1349353).

21460247 is a wasteful number, since it uses less digits than its factorization.

21460247 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 286.

The product of its (nonzero) digits is 2688, while the sum is 26.

The square root of 21460247 is about 4632.5205881895. The cubic root of 21460247 is about 277.8934040885.

Adding to 21460247 its reverse (74206412), we get a palindrome (95666659).

The spelling of 21460247 in words is "twenty-one million, four hundred sixty thousand, two hundred forty-seven".