21470465 has 8 divisors (see below), whose sum is σ = 26030760. Its totient is φ = 16998912.

The previous prime is 21470461. The next prime is 21470467. The reversal of 21470465 is 56407412.

It can be written as a sum of positive squares in 4 ways, for example, as 7392961 + 14077504 = 2719^2 + 3752^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21470465 - 2² = 21470461 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21470461) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 21650 + ... + 22619.

It is an arithmetic number, because the mean of its divisors is an integer number (3253845).

Almost surely, 2^21470465 is an apocalyptic number.

It is an amenable number.

21470465 is a deficient number, since it is larger than the sum of its proper divisors (4560295).

21470465 is an equidigital number, since it uses as much as digits as its factorization.

21470465 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 44371.

The product of its (nonzero) digits is 6720, while the sum is 29.

The square root of 21470465 is about 4633.6233122687. The cubic root of 21470465 is about 277.9375021249.

Adding to 21470465 its reverse (56407412), we get a palindrome (77877877).

The spelling of 21470465 in words is "twenty-one million, four hundred seventy thousand, four hundred sixty-five".