990900019 has 2 divisors, whose sum is σ = 990900020. Its totient is φ = 990900018.

The previous prime is 990899999. The next prime is 990900023. The reversal of 990900019 is 910009099.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-990900019 is a prime.

It is a super-2 number, since 2×990900019² = 1963765695308400722, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (990900049) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 495450009 + 495450010.

It is an arithmetic number, because the mean of its divisors is an integer number (495450010).

Almost surely, 2^990900019 is an apocalyptic number.

990900019 is a deficient number, since it is larger than the sum of its proper divisors (1).

990900019 is an equidigital number, since it uses as much as digits as its factorization.

990900019 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 6561, while the sum is 37.

The square root of 990900019 is about 31478.5644367719. The cubic root of 990900019 is about 996.9574251268.

The spelling of 990900019 in words is "nine hundred ninety million, nine hundred thousand, nineteen".