20131745 has 8 divisors (see below), whose sum is σ = 24672384. Its totient is φ = 15762544.

The previous prime is 20131717. The next prime is 20131753. The reversal of 20131745 is 54713102.

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 20131745 - 2⁶ = 20131681 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 20131745.

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 7 ways as a sum of consecutive naturals, for example, 42599 + ... + 43068.

It is an arithmetic number, because the mean of its divisors is an integer number (3084048).

Almost surely, 2^20131745 is an apocalyptic number.

It is an amenable number.

20131745 is a deficient number, since it is larger than the sum of its proper divisors (4540639).

20131745 is an equidigital number, since it uses as much as digits as its factorization.

20131745 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 85719.

The product of its (nonzero) digits is 840, while the sum is 23.

The square root of 20131745 is about 4486.8413165611. The cubic root of 20131745 is about 272.0364759690.

Adding to 20131745 its reverse (54713102), we get a palindrome (74844847).

The spelling of 20131745 in words is "twenty million, one hundred thirty-one thousand, seven hundred forty-five".