999211722973 has 4 divisors (see below), whose sum is σ = 999218676348. Its totient is φ = 999204769600.

The previous prime is 999211722893. The next prime is 999211722983. The reversal of 999211722973 is 379227112999.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 895442053284 + 103769669689 = 946278^2 + 322133^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-999211722973 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (999211722983) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3256486 + ... + 3550087.

It is an arithmetic number, because the mean of its divisors is an integer number (249804669087).

Almost surely, 2^999211722973 is an apocalyptic number.

It is an amenable number.

999211722973 is a deficient number, since it is larger than the sum of its proper divisors (6953375).

999211722973 is a wasteful number, since it uses less digits than its factorization.

999211722973 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6953374.

The product of its digits is 7715736, while the sum is 61.

The spelling of 999211722973 in words is "nine hundred ninety-nine billion, two hundred eleven million, seven hundred twenty-two thousand, nine hundred seventy-three".