651406321 has 2 divisors, whose sum is σ = 651406322. Its totient is φ = 651406320.

The previous prime is 651406297. The next prime is 651406331. The reversal of 651406321 is 123604156.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 603242721 + 48163600 = 24561^2 + 6940^2 .

It is a cyclic number.

It is not a de Polignac number, because 651406321 - 2⁹ = 651405809 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 651406321.

It is not a weakly prime, because it can be changed into another prime (651406331) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 325703160 + 325703161.

It is an arithmetic number, because the mean of its divisors is an integer number (325703161).

Almost surely, 2^651406321 is an apocalyptic number.

It is an amenable number.

651406321 is a deficient number, since it is larger than the sum of its proper divisors (1).

651406321 is an equidigital number, since it uses as much as digits as its factorization.

651406321 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 4320, while the sum is 28.

The square root of 651406321 is about 25522.6628900669. The cubic root of 651406321 is about 866.8633785399.

The spelling of 651406321 in words is "six hundred fifty-one million, four hundred six thousand, three hundred twenty-one".