20816465 has 8 divisors (see below), whose sum is σ = 25162920. Its totient is φ = 16531072.

The previous prime is 20816437. The next prime is 20816489. The reversal of 20816465 is 56461802.

It can be written as a sum of positive squares in 4 ways, for example, as 4227136 + 16589329 = 2056^2 + 4073^2 .

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 20816465 - 2¹⁰ = 20815441 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 14510 + ... + 15879.

It is an arithmetic number, because the mean of its divisors is an integer number (3145365).

Almost surely, 2^20816465 is an apocalyptic number.

It is an amenable number.

20816465 is a deficient number, since it is larger than the sum of its proper divisors (4346455).

20816465 is a wasteful number, since it uses less digits than its factorization.

20816465 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 30531.

The product of its (nonzero) digits is 11520, while the sum is 32.

The square root of 20816465 is about 4562.5064383516. The cubic root of 20816465 is about 275.0863200095.

The spelling of 20816465 in words is "twenty million, eight hundred sixteen thousand, four hundred sixty-five".