2501538821 has 2 divisors, whose sum is σ = 2501538822. Its totient is φ = 2501538820.

The previous prime is 2501538791. The next prime is 2501538847. The reversal of 2501538821 is 1288351052.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1682148196 + 819390625 = 41014^2 + 28625^2 .

It is a cyclic number.

It is not a de Polignac number, because 2501538821 - 2²² = 2497344517 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2501537821) 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 as a sum of consecutive naturals, namely, 1250769410 + 1250769411.

It is an arithmetic number, because the mean of its divisors is an integer number (1250769411).

Almost surely, 2^2501538821 is an apocalyptic number.

It is an amenable number.

2501538821 is a deficient number, since it is larger than the sum of its proper divisors (1).

2501538821 is an equidigital number, since it uses as much as digits as its factorization.

2501538821 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 19200, while the sum is 35.

The square root of 2501538821 is about 50015.3858427584. The cubic root of 2501538821 is about 1357.4872180376.

Adding to 2501538821 its reverse (1288351052), we get a palindrome (3789889873).

It can be divided in two parts, 25015 and 38821, that added together give a palindrome (63836).

The spelling of 2501538821 in words is "two billion, five hundred one million, five hundred thirty-eight thousand, eight hundred twenty-one".