6405690251 has 2 divisors, whose sum is σ = 6405690252. Its totient is φ = 6405690250.

The previous prime is 6405690223. The next prime is 6405690281. The reversal of 6405690251 is 1520965046.

6405690251 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-6405690251 is a prime.

It is a Sophie Germain prime.

It is not a weakly prime, because it can be changed into another prime (6405690281) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3202845125 + 3202845126.

It is an arithmetic number, because the mean of its divisors is an integer number (3202845126).

Almost surely, 2^6405690251 is an apocalyptic number.

6405690251 is a deficient number, since it is larger than the sum of its proper divisors (1).

6405690251 is an equidigital number, since it uses as much as digits as its factorization.

6405690251 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 64800, while the sum is 38.

The square root of 6405690251 is about 80035.5561672436. The cubic root of 6405690251 is about 1857.1856163987.

The spelling of 6405690251 in words is "six billion, four hundred five million, six hundred ninety thousand, two hundred fifty-one".