651807491 has 2 divisors, whose sum is σ = 651807492. Its totient is φ = 651807490.

The previous prime is 651807469. The next prime is 651807529. The reversal of 651807491 is 194708156.

651807491 is digitally balanced in base 2, 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-651807491 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (651807461) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 325903745 + 325903746.

It is an arithmetic number, because the mean of its divisors is an integer number (325903746).

Almost surely, 2^651807491 is an apocalyptic number.

651807491 is a deficient number, since it is larger than the sum of its proper divisors (1).

651807491 is an equidigital number, since it uses as much as digits as its factorization.

651807491 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 60480, while the sum is 41.

The square root of 651807491 is about 25530.5207741636. The cubic root of 651807491 is about 867.0412952540.

The spelling of 651807491 in words is "six hundred fifty-one million, eight hundred seven thousand, four hundred ninety-one".