999990973 has 2 divisors, whose sum is σ = 999990974. Its totient is φ = 999990972.

The previous prime is 999990947. The next prime is 999990977. The reversal of 999990973 is 379099999.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 832495609 + 167495364 = 28853^2 + 12942^2 .

It is a cyclic number.

It is not a de Polignac number, because 999990973 - 2⁹ = 999990461 is a prime.

It is a super-3 number, since 3×999990973³ (a number of 28 digits) contains 333 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (999990977) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 499995486 + 499995487.

It is an arithmetic number, because the mean of its divisors is an integer number (499995487).

Almost surely, 2^999990973 is an apocalyptic number.

It is an amenable number.

999990973 is a deficient number, since it is larger than the sum of its proper divisors (1).

999990973 is an equidigital number, since it uses as much as digits as its factorization.

999990973 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 11160261, while the sum is 64.

The square root of 999990973 is about 31622.6338719595. The cubic root of 999990973 is about 999.9969909909.

The spelling of 999990973 in words is "nine hundred ninety-nine million, nine hundred ninety thousand, nine hundred seventy-three".