21168465 has 16 divisors (see below), whose sum is σ = 34509888. Its totient is φ = 11076416.

The previous prime is 21168461. The next prime is 21168479. The reversal of 21168465 is 56486112.

It is a cyclic number.

It is not a de Polignac number, because 21168465 - 2² = 21168461 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21168461) 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, 12519 + ... + 14108.

It is an arithmetic number, because the mean of its divisors is an integer number (2156868).

Almost surely, 2^21168465 is an apocalyptic number.

It is an amenable number.

21168465 is a deficient number, since it is larger than the sum of its proper divisors (13341423).

21168465 is a wasteful number, since it uses less digits than its factorization.

21168465 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 26688.

The product of its digits is 11520, while the sum is 33.

The square root of 21168465 is about 4600.9200166923. The cubic root of 21168465 is about 276.6282030688.

The spelling of 21168465 in words is "twenty-one million, one hundred sixty-eight thousand, four hundred sixty-five".