90999899 has 2 divisors, whose sum is σ = 90999900. Its totient is φ = 90999898.

The previous prime is 90999859. The next prime is 90999947. The reversal of 90999899 is 99899909.

It is a weak prime.

It is an emirp because it is prime and its reverse (99899909) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 90999899 - 2¹² = 90995803 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (90999859) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45499949 + 45499950.

It is an arithmetic number, because the mean of its divisors is an integer number (45499950).

Almost surely, 2^90999899 is an apocalyptic number.

90999899 is a deficient number, since it is larger than the sum of its proper divisors (1).

90999899 is an equidigital number, since it uses as much as digits as its factorization.

90999899 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 4251528, while the sum is 62.

The square root of 90999899 is about 9539.3867203296. The cubic root of 90999899 is about 449.7939781201.

The spelling of 90999899 in words is "ninety million, nine hundred ninety-nine thousand, eight hundred ninety-nine".