20501263 has 6 divisors (see below), whose sum is σ = 20816376. Its totient is φ = 20190852.

The previous prime is 20501237. The next prime is 20501267. The reversal of 20501263 is 36210502.

It is a happy number.

It is a de Polignac number, because none of the positive numbers 2^k-20501263 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 20501263.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20501267) by changing a digit.

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 5 ways as a sum of consecutive naturals, for example, 2206 + ... + 6772.

It is an arithmetic number, because the mean of its divisors is an integer number (3469396).

Almost surely, 2^20501263 is an apocalyptic number.

20501263 is a deficient number, since it is larger than the sum of its proper divisors (315113).

20501263 is an frugal number, since it uses more digits than its factorization.

20501263 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4701 (or 4634 counting only the distinct ones).

The product of its (nonzero) digits is 360, while the sum is 19.

The square root of 20501263 is about 4527.8320419380. The cubic root of 20501263 is about 273.6908041836.

Adding to 20501263 its reverse (36210502), we get a palindrome (56711765).

The spelling of 20501263 in words is "twenty million, five hundred one thousand, two hundred sixty-three".