999061891 has 2 divisors, whose sum is σ = 999061892. Its totient is φ = 999061890.

The previous prime is 999061859. The next prime is 999061897. The reversal of 999061891 is 198160999.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 999061891 - 2⁵ = 999061859 is a prime.

It is not a weakly prime, because it can be changed into another prime (999061897) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 499530945 + 499530946.

It is an arithmetic number, because the mean of its divisors is an integer number (499530946).

Almost surely, 2^999061891 is an apocalyptic number.

999061891 is a deficient number, since it is larger than the sum of its proper divisors (1).

999061891 is an equidigital number, since it uses as much as digits as its factorization.

999061891 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 314928, while the sum is 52.

The square root of 999061891 is about 31607.9403156865. The cubic root of 999061891 is about 999.6871991658.

The spelling of 999061891 in words is "nine hundred ninety-nine million, sixty-one thousand, eight hundred ninety-one".