99491609 has 16 divisors (see below), whose sum is σ = 116467200. Its totient is φ = 84954240.

The previous prime is 99491591. The next prime is 99491659. The reversal of 99491609 is 90619499.

It is not a de Polignac number, because 99491609 - 2¹² = 99487513 is a prime.

It is a super-2 number, since 2×99491609² = 19797160522817762, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (99491659) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 147497 + ... + 148169.

It is an arithmetic number, because the mean of its divisors is an integer number (7279200).

Almost surely, 2^99491609 is an apocalyptic number.

It is an amenable number.

99491609 is a deficient number, since it is larger than the sum of its proper divisors (16975591).

99491609 is an equidigital number, since it uses as much as digits as its factorization.

99491609 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1125 (or 1111 counting only the distinct ones).

The product of its (nonzero) digits is 157464, while the sum is 47.

The square root of 99491609 is about 9974.5480599374. The cubic root of 99491609 is about 463.3709659523.

The spelling of 99491609 in words is "ninety-nine million, four hundred ninety-one thousand, six hundred nine".