20112645 has 64 divisors (see below), whose sum is σ = 39223296. Its totient is φ = 8605440.

The previous prime is 20112641. The next prime is 20112661. The reversal of 20112645 is 54621102.

It is not a de Polignac number, because 20112645 - 2² = 20112641 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20112641) 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 63 ways as a sum of consecutive naturals, for example, 120352 + ... + 120518.

It is an arithmetic number, because the mean of its divisors is an integer number (612864).

Almost surely, 2^20112645 is an apocalyptic number.

It is an amenable number.

20112645 is a deficient number, since it is larger than the sum of its proper divisors (19110651).

20112645 is a wasteful number, since it uses less digits than its factorization.

20112645 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 250.

The product of its (nonzero) digits is 480, while the sum is 21.

The square root of 20112645 is about 4484.7123653586. The cubic root of 20112645 is about 271.9504171804.

Adding to 20112645 its reverse (54621102), we get a palindrome (74733747).

It can be divided in two parts, 2011 and 2645, that added together give a triangular number (4656 = T₉₆).

The spelling of 20112645 in words is "twenty million, one hundred twelve thousand, six hundred forty-five".