3125513021 has 2 divisors, whose sum is σ = 3125513022. Its totient is φ = 3125513020.

The previous prime is 3125513003. The next prime is 3125513051. The reversal of 3125513021 is 1203155213.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 2822265625 + 303247396 = 53125^2 + 17414^2 .

It is a cyclic number.

It is not a de Polignac number, because 3125513021 - 2²⁶ = 3058404157 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (3125513051) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1562756510 + 1562756511.

It is an arithmetic number, because the mean of its divisors is an integer number (1562756511).

Almost surely, 2^3125513021 is an apocalyptic number.

It is an amenable number.

3125513021 is a deficient number, since it is larger than the sum of its proper divisors (1).

3125513021 is an equidigital number, since it uses as much as digits as its factorization.

3125513021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 900, while the sum is 23.

The square root of 3125513021 is about 55906.2878485059. The cubic root of 3125513021 is about 1462.0888691290.

Adding to 3125513021 its reverse (1203155213), we get a palindrome (4328668234).

The spelling of 3125513021 in words is "three billion, one hundred twenty-five million, five hundred thirteen thousand, twenty-one".