1091645651 has 2 divisors, whose sum is σ = 1091645652. Its totient is φ = 1091645650.

The previous prime is 1091645647. The next prime is 1091645677. The reversal of 1091645651 is 1565461901.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 1091645651 - 2² = 1091645647 is a prime.

It is not a weakly prime, because it can be changed into another prime (1091648651) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 545822825 + 545822826.

It is an arithmetic number, because the mean of its divisors is an integer number (545822826).

Almost surely, 2^1091645651 is an apocalyptic number.

1091645651 is a deficient number, since it is larger than the sum of its proper divisors (1).

1091645651 is an equidigital number, since it uses as much as digits as its factorization.

1091645651 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 32400, while the sum is 38.

The square root of 1091645651 is about 33040.0613044225. The cubic root of 1091645651 is about 1029.6601294835.

The spelling of 1091645651 in words is "one billion, ninety-one million, six hundred forty-five thousand, six hundred fifty-one".