21460645 has 4 divisors (see below), whose sum is σ = 25752780. Its totient is φ = 17168512.

The previous prime is 21460643. The next prime is 21460657. The reversal of 21460645 is 54606412.

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 9941409 + 11519236 = 3153^2 + 3394^2 .

It is a cyclic number.

It is not a de Polignac number, because 21460645 - 2¹ = 21460643 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21460643) 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, 2146060 + ... + 2146069.

It is an arithmetic number, because the mean of its divisors is an integer number (6438195).

Almost surely, 2^21460645 is an apocalyptic number.

It is an amenable number.

21460645 is a deficient number, since it is larger than the sum of its proper divisors (4292135).

21460645 is an equidigital number, since it uses as much as digits as its factorization.

21460645 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4292134.

The product of its (nonzero) digits is 5760, while the sum is 28.

The square root of 21460645 is about 4632.5635451659. The cubic root of 21460645 is about 277.8951220074.

The spelling of 21460645 in words is "twenty-one million, four hundred sixty thousand, six hundred forty-five".