990761521 has 2 divisors, whose sum is σ = 990761522. Its totient is φ = 990761520.

The previous prime is 990761467. The next prime is 990761549. The reversal of 990761521 is 125167099.

990761521 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 891858496 + 98903025 = 29864^2 + 9945^2 .

It is a cyclic number.

It is not a de Polignac number, because 990761521 - 2¹⁷ = 990630449 is a prime.

It is not a weakly prime, because it can be changed into another prime (990761591) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 495380760 + 495380761.

It is an arithmetic number, because the mean of its divisors is an integer number (495380761).

Almost surely, 2^990761521 is an apocalyptic number.

It is an amenable number.

990761521 is a deficient number, since it is larger than the sum of its proper divisors (1).

990761521 is an equidigital number, since it uses as much as digits as its factorization.

990761521 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 34020, while the sum is 40.

The square root of 990761521 is about 31476.3644819410. The cubic root of 990761521 is about 996.9109747482.

The spelling of 990761521 in words is "nine hundred ninety million, seven hundred sixty-one thousand, five hundred twenty-one".