6402905921 has 2 divisors, whose sum is σ = 6402905922. Its totient is φ = 6402905920.

The previous prime is 6402905903. The next prime is 6402905983. The reversal of 6402905921 is 1295092046.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 5118687025 + 1284218896 = 71545^2 + 35836^2 .

It is a cyclic number.

It is not a de Polignac number, because 6402905921 - 2¹⁰ = 6402904897 is a prime.

It is not a weakly prime, because it can be changed into another prime (6402908921) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3201452960 + 3201452961.

It is an arithmetic number, because the mean of its divisors is an integer number (3201452961).

Almost surely, 2^6402905921 is an apocalyptic number.

It is an amenable number.

6402905921 is a deficient number, since it is larger than the sum of its proper divisors (1).

6402905921 is an equidigital number, since it uses as much as digits as its factorization.

6402905921 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 38880, while the sum is 38.

The square root of 6402905921 is about 80018.1599451025. The cubic root of 6402905921 is about 1856.9164928109.

Adding to 6402905921 its reverse (1295092046), we get a palindrome (7697997967).

The spelling of 6402905921 in words is "six billion, four hundred two million, nine hundred five thousand, nine hundred twenty-one".