20523601 has 6 divisors (see below), whose sum is σ = 23874450. Its totient is φ = 17591616.

The previous prime is 20523593. The next prime is 20523611. The reversal of 20523601 is 10632502.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 19140625 + 1382976 = 4375^2 + 1176^2 .

It is not a de Polignac number, because 20523601 - 2³ = 20523593 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20523611) 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 5 ways as a sum of consecutive naturals, for example, 209376 + ... + 209473.

It is an arithmetic number, because the mean of its divisors is an integer number (3979075).

Almost surely, 2^20523601 is an apocalyptic number.

It is an amenable number.

20523601 is a deficient number, since it is larger than the sum of its proper divisors (3350849).

20523601 is an equidigital number, since it uses as much as digits as its factorization.

20523601 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 418863 (or 418856 counting only the distinct ones).

The product of its (nonzero) digits is 360, while the sum is 19.

The square root of 20523601 is about 4530.2981138111. The cubic root of 20523601 is about 273.7901718185.

The spelling of 20523601 in words is "twenty million, five hundred twenty-three thousand, six hundred one".