20181265 has 8 divisors (see below), whose sum is σ = 26080488. Its totient is φ = 14903040.

The previous prime is 20181247. The next prime is 20181311. The reversal of 20181265 is 56218102.

It can be written as a sum of positive squares in 4 ways, for example, as 1871424 + 18309841 = 1368^2 + 4279^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 20181265 - 2¹¹ = 20179217 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 155176 + ... + 155305.

It is an arithmetic number, because the mean of its divisors is an integer number (3260061).

Almost surely, 2^20181265 is an apocalyptic number.

It is an amenable number.

20181265 is a deficient number, since it is larger than the sum of its proper divisors (5899223).

20181265 is a wasteful number, since it uses less digits than its factorization.

20181265 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 310499.

The product of its (nonzero) digits is 960, while the sum is 25.

The square root of 20181265 is about 4492.3562859595. The cubic root of 20181265 is about 272.2593448071.

Adding to 20181265 its reverse (56218102), we get a palindrome (76399367).

The spelling of 20181265 in words is "twenty million, one hundred eighty-one thousand, two hundred sixty-five".