20636465 has 4 divisors (see below), whose sum is σ = 24763764. Its totient is φ = 16509168.

The previous prime is 20636461. The next prime is 20636479. The reversal of 20636465 is 56463602.

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 14799409 + 5837056 = 3847^2 + 2416^2 .

It is a cyclic number.

It is not a de Polignac number, because 20636465 - 2² = 20636461 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20636461) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2063642 + ... + 2063651.

It is an arithmetic number, because the mean of its divisors is an integer number (6190941).

Almost surely, 2^20636465 is an apocalyptic number.

It is an amenable number.

20636465 is a deficient number, since it is larger than the sum of its proper divisors (4127299).

20636465 is an equidigital number, since it uses as much as digits as its factorization.

20636465 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4127298.

The product of its (nonzero) digits is 25920, while the sum is 32.

The square root of 20636465 is about 4542.7376107365. The cubic root of 20636465 is about 274.2911330026.

The spelling of 20636465 in words is "twenty million, six hundred thirty-six thousand, four hundred sixty-five".