1651651691 has 2 divisors, whose sum is σ = 1651651692. Its totient is φ = 1651651690.

The previous prime is 1651651601. The next prime is 1651651693. The reversal of 1651651691 is 1961561561.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1651651691 - 2¹⁰ = 1651650667 is a prime.

It is a Sophie Germain prime.

Together with 1651651693, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (1651651693) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 825825845 + 825825846.

It is an arithmetic number, because the mean of its divisors is an integer number (825825846).

Almost surely, 2^1651651691 is an apocalyptic number.

1651651691 is a deficient number, since it is larger than the sum of its proper divisors (1).

1651651691 is an equidigital number, since it uses as much as digits as its factorization.

1651651691 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 48600, while the sum is 41.

The square root of 1651651691 is about 40640.5178485708. The cubic root of 1651651691 is about 1182.0599112348.

The spelling of 1651651691 in words is "one billion, six hundred fifty-one million, six hundred fifty-one thousand, six hundred ninety-one".