20163745 has 12 divisors (see below), whose sum is σ = 28147284. Its totient is φ = 13826400.

The previous prime is 20163739. The next prime is 20163749. The reversal of 20163745 is 54736102.

20163745 = T₂₇₇ + T₂₇₈ + ... + T₅₂₁.

It can be written as a sum of positive squares in 2 ways, for example, as 10504081 + 9659664 = 3241^2 + 3108^2 .

It is not a de Polignac number, because 20163745 - 2¹¹ = 20161697 is a prime.

It is a super-2 number, since 2×20163745² = 813153224850050, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20163749) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 40906 + ... + 41395.

It is an arithmetic number, because the mean of its divisors is an integer number (2345607).

Almost surely, 2^20163745 is an apocalyptic number.

It is an amenable number.

20163745 is a deficient number, since it is larger than the sum of its proper divisors (7983539).

20163745 is an equidigital number, since it uses as much as digits as its factorization.

20163745 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 82320 (or 82313 counting only the distinct ones).

The product of its (nonzero) digits is 5040, while the sum is 28.

The square root of 20163745 is about 4490.4058836591. The cubic root of 20163745 is about 272.1805363229.

Adding to 20163745 its reverse (54736102), we get a palindrome (74899847).

The spelling of 20163745 in words is "twenty million, one hundred sixty-three thousand, seven hundred forty-five".