991291002043 has 2 divisors, whose sum is σ = 991291002044. Its totient is φ = 991291002042.

The previous prime is 991291001977. The next prime is 991291002049. The reversal of 991291002043 is 340200192199.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 991291002043 - 2¹⁷ = 991290870971 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 991291001987 and 991291002005.

It is not a weakly prime, because it can be changed into another prime (991291002049) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 495645501021 + 495645501022.

It is an arithmetic number, because the mean of its divisors is an integer number (495645501022).

Almost surely, 2^991291002043 is an apocalyptic number.

991291002043 is a deficient number, since it is larger than the sum of its proper divisors (1).

991291002043 is an equidigital number, since it uses as much as digits as its factorization.

991291002043 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 34992, while the sum is 40.

The spelling of 991291002043 in words is "nine hundred ninety-one billion, two hundred ninety-one million, two thousand, forty-three".