20645601 has 8 divisors (see below), whose sum is σ = 27549024. Its totient is φ = 13752960.

The previous prime is 20645579. The next prime is 20645671. The reversal of 20645601 is 10654602.

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

It is not a de Polignac number, because 20645601 - 2¹⁵ = 20612833 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (20645671) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4590 + ... + 7896.

It is an arithmetic number, because the mean of its divisors is an integer number (3443628).

Almost surely, 2^20645601 is an apocalyptic number.

It is an amenable number.

20645601 is a deficient number, since it is larger than the sum of its proper divisors (6903423).

20645601 is a wasteful number, since it uses less digits than its factorization.

20645601 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5391.

The product of its (nonzero) digits is 1440, while the sum is 24.

The square root of 20645601 is about 4543.7430605174. The cubic root of 20645601 is about 274.3316043087.

Subtracting from 20645601 its reverse (10654602), we obtain a palindrome (9990999).

The spelling of 20645601 in words is "twenty million, six hundred forty-five thousand, six hundred one".