1665322232891 has 2 divisors, whose sum is σ = 1665322232892. Its totient is φ = 1665322232890.

The previous prime is 1665322232813. The next prime is 1665322232897. The reversal of 1665322232891 is 1982322235661.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1665322232891 - 2¹⁴ = 1665322216507 is a prime.

It is a super-2 number, since 2×1665322232891² (a number of 25 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (1665322232897) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 832661116445 + 832661116446.

It is an arithmetic number, because the mean of its divisors is an integer number (832661116446).

Almost surely, 2^{1665322232891} is an apocalyptic number.

1665322232891 is a deficient number, since it is larger than the sum of its proper divisors (1).

1665322232891 is an equidigital number, since it uses as much as digits as its factorization.

1665322232891 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1866240, while the sum is 50.

The spelling of 1665322232891 in words is "one trillion, six hundred sixty-five billion, three hundred twenty-two million, two hundred thirty-two thousand, eight hundred ninety-one".