999220973 has 2 divisors, whose sum is σ = 999220974. Its totient is φ = 999220972.

The previous prime is 999220967. The next prime is 999221009. The reversal of 999220973 is 379022999.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 735385924 + 263835049 = 27118^2 + 16243^2 .

It is an emirp because it is prime and its reverse (379022999) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 999220973 - 2¹² = 999216877 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (999220933) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 499610486 + 499610487.

It is an arithmetic number, because the mean of its divisors is an integer number (499610487).

Almost surely, 2^999220973 is an apocalyptic number.

It is an amenable number.

999220973 is a deficient number, since it is larger than the sum of its proper divisors (1).

999220973 is an equidigital number, since it uses as much as digits as its factorization.

999220973 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 551124, while the sum is 50.

The square root of 999220973 is about 31610.4567034391. The cubic root of 999220973 is about 999.7402568727.

The spelling of 999220973 in words is "nine hundred ninety-nine million, two hundred twenty thousand, nine hundred seventy-three".