63121813 has 2 divisors, whose sum is σ = 63121814. Its totient is φ = 63121812.

The previous prime is 63121801. The next prime is 63121823. The reversal of 63121813 is 31812136.

63121813 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 61826769 + 1295044 = 7863^2 + 1138^2 .

It is a cyclic number.

It is not a de Polignac number, because 63121813 - 2²¹ = 61024661 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (63121823) 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, 31560906 + 31560907.

It is an arithmetic number, because the mean of its divisors is an integer number (31560907).

Almost surely, 2^63121813 is an apocalyptic number.

It is an amenable number.

63121813 is a deficient number, since it is larger than the sum of its proper divisors (1).

63121813 is an equidigital number, since it uses as much as digits as its factorization.

63121813 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 864, while the sum is 25.

The square root of 63121813 is about 7944.9237252475. The cubic root of 63121813 is about 398.1620111784.

Adding to 63121813 its reverse (31812136), we get a palindrome (94933949).

The spelling of 63121813 in words is "sixty-three million, one hundred twenty-one thousand, eight hundred thirteen".