20101745 has 4 divisors (see below), whose sum is σ = 24122100. Its totient is φ = 16081392.

The previous prime is 20101721. The next prime is 20101771. The reversal of 20101745 is 54710102.

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 15936064 + 4165681 = 3992^2 + 2041^2 .

It is a cyclic number.

It is not a de Polignac number, because 20101745 - 2¹⁰ = 20100721 is a prime.

It is a Curzon number.

It is an unprimeable number.

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, 2010170 + ... + 2010179.

It is an arithmetic number, because the mean of its divisors is an integer number (6030525).

Almost surely, 2^20101745 is an apocalyptic number.

It is an amenable number.

20101745 is a deficient number, since it is larger than the sum of its proper divisors (4020355).

20101745 is an equidigital number, since it uses as much as digits as its factorization.

20101745 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4020354.

The product of its (nonzero) digits is 280, while the sum is 20.

The square root of 20101745 is about 4483.4969610785. The cubic root of 20101745 is about 271.9012806761.

Adding to 20101745 its reverse (54710102), we get a palindrome (74811847).

The spelling of 20101745 in words is "twenty million, one hundred one thousand, seven hundred forty-five".