999423737891 has 2 divisors, whose sum is σ = 999423737892. Its totient is φ = 999423737890.

The previous prime is 999423737867. The next prime is 999423737899. The reversal of 999423737891 is 198737324999.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 999423737891 - 2¹⁴ = 999423721507 is a prime.

It is not a weakly prime, because it can be changed into another prime (999423737899) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 499711868945 + 499711868946.

It is an arithmetic number, because the mean of its divisors is an integer number (499711868946).

Almost surely, 2^999423737891 is an apocalyptic number.

999423737891 is a deficient number, since it is larger than the sum of its proper divisors (1).

999423737891 is an equidigital number, since it uses as much as digits as its factorization.

999423737891 is an evil number, because the sum of its binary digits is even.

The product of its digits is 185177664, while the sum is 71.

The spelling of 999423737891 in words is "nine hundred ninety-nine billion, four hundred twenty-three million, seven hundred thirty-seven thousand, eight hundred ninety-one".