99191641 has 4 divisors (see below), whose sum is σ = 99441892. Its totient is φ = 98941392.

The previous prime is 99191639. The next prime is 99191671. The reversal of 99191641 is 14619199.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 84713616 + 14478025 = 9204^2 + 3805^2 .

It is a cyclic number.

It is not a de Polignac number, because 99191641 - 2¹ = 99191639 is a prime.

It is the 9960-th Hogben number.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 99191594 and 99191603.

It is not an unprimeable number, because it can be changed into a prime (99191671) by changing a digit.

It is a nontrivial repunit in base 9959.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 124530 + ... + 125323.

It is an arithmetic number, because the mean of its divisors is an integer number (24860473).

Almost surely, 2^99191641 is an apocalyptic number.

It is an amenable number.

99191641 is a deficient number, since it is larger than the sum of its proper divisors (250251).

99191641 is a wasteful number, since it uses less digits than its factorization.

99191641 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 250250.

The product of its digits is 17496, while the sum is 40.

The square root of 99191641 is about 9959.5000376525. The cubic root of 99191641 is about 462.9048080871.

The spelling of 99191641 in words is "ninety-nine million, one hundred ninety-one thousand, six hundred forty-one".