990430549 has 2 divisors, whose sum is σ = 990430550. Its totient is φ = 990430548.

The previous prime is 990430513. The next prime is 990430561. The reversal of 990430549 is 945034099.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 971568900 + 18861649 = 31170^2 + 4343^2 .

It is a cyclic number.

It is not a de Polignac number, because 990430549 - 2⁹ = 990430037 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (990430589) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 495215274 + 495215275.

It is an arithmetic number, because the mean of its divisors is an integer number (495215275).

Almost surely, 2^990430549 is an apocalyptic number.

It is an amenable number.

990430549 is a deficient number, since it is larger than the sum of its proper divisors (1).

990430549 is an equidigital number, since it uses as much as digits as its factorization.

990430549 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 174960, while the sum is 43.

The square root of 990430549 is about 31471.1065741261. The cubic root of 990430549 is about 996.7999536263.

The spelling of 990430549 in words is "nine hundred ninety million, four hundred thirty thousand, five hundred forty-nine".