99991577 has 8 divisors (see below), whose sum is σ = 115454976. Its totient is φ = 84822912.

The previous prime is 99991561. The next prime is 99991583. The reversal of 99991577 is 77519999.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 99991577 - 2⁴ = 99991561 is a prime.

It is not an unprimeable number, because it can be changed into a prime (99991517) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 72953 + ... + 74310.

It is an arithmetic number, because the mean of its divisors is an integer number (14431872).

Almost surely, 2^99991577 is an apocalyptic number.

99991577 is a gapful number since it is divisible by the number (97) formed by its first and last digit.

It is an amenable number.

99991577 is a deficient number, since it is larger than the sum of its proper divisors (15463399).

99991577 is a wasteful number, since it uses less digits than its factorization.

99991577 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 147367.

The product of its digits is 1607445, while the sum is 56.

The square root of 99991577 is about 9999.5788411313. The cubic root of 99991577 is about 464.1458509611.

The spelling of 99991577 in words is "ninety-nine million, nine hundred ninety-one thousand, five hundred seventy-seven".