1091645647 has 2 divisors, whose sum is σ = 1091645648. Its totient is φ = 1091645646.

The previous prime is 1091645617. The next prime is 1091645651. The reversal of 1091645647 is 7465461901.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1091645647 - 2¹¹ = 1091643599 is a prime.

It is a super-2 number, since 2×1091645647² = 2383380437228097218, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1091645617) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 545822823 + 545822824.

It is an arithmetic number, because the mean of its divisors is an integer number (545822824).

Almost surely, 2^1091645647 is an apocalyptic number.

1091645647 is a deficient number, since it is larger than the sum of its proper divisors (1).

1091645647 is an equidigital number, since it uses as much as digits as its factorization.

1091645647 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 181440, while the sum is 43.

The square root of 1091645647 is about 33040.0612438900. The cubic root of 1091645647 is about 1029.6601282259.

The spelling of 1091645647 in words is "one billion, ninety-one million, six hundred forty-five thousand, six hundred forty-seven".