99903581 has 2 divisors, whose sum is σ = 99903582. Its totient is φ = 99903580.

The previous prime is 99903547. The next prime is 99903703. The reversal of 99903581 is 18530999.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 99400900 + 502681 = 9970^2 + 709^2 .

It is a cyclic number.

It is not a de Polignac number, because 99903581 - 2²² = 95709277 is a prime.

It is a super-2 number, since 2×99903581² = 19961450993247122, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Chen prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (99903281) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 49951790 + 49951791.

It is an arithmetic number, because the mean of its divisors is an integer number (49951791).

Almost surely, 2^99903581 is an apocalyptic number.

It is an amenable number.

99903581 is a deficient number, since it is larger than the sum of its proper divisors (1).

99903581 is an equidigital number, since it uses as much as digits as its factorization.

99903581 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 87480, while the sum is 44.

The square root of 99903581 is about 9995.1778873615. The cubic root of 99903581 is about 464.0096562720.

The spelling of 99903581 in words is "ninety-nine million, nine hundred three thousand, five hundred eighty-one".