999981403 has 2 divisors, whose sum is σ = 999981404. Its totient is φ = 999981402.

The previous prime is 999981397. The next prime is 999981413. The reversal of 999981403 is 304189999.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 999981403 - 2¹⁷ = 999850331 is a prime.

It is not a weakly prime, because it can be changed into another prime (999981413) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 499990701 + 499990702.

It is an arithmetic number, because the mean of its divisors is an integer number (499990702).

Almost surely, 2^999981403 is an apocalyptic number.

999981403 is a deficient number, since it is larger than the sum of its proper divisors (1).

999981403 is an equidigital number, since it uses as much as digits as its factorization.

999981403 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 629856, while the sum is 52.

The square root of 999981403 is about 31622.4825559285. The cubic root of 999981403 is about 999.9938009616.

The spelling of 999981403 in words is "nine hundred ninety-nine million, nine hundred eighty-one thousand, four hundred three".