99861391 has 8 divisors (see below), whose sum is σ = 114197120. Its totient is φ = 85543128.

The previous prime is 99861389. The next prime is 99861401. The reversal of 99861391 is 19316899.

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 99861391 - 2¹ = 99861389 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (99861301) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 11980 + ... + 18526.

It is an arithmetic number, because the mean of its divisors is an integer number (14274640).

Almost surely, 2^99861391 is an apocalyptic number.

99861391 is the 5770-th hex number.

99861391 is a deficient number, since it is larger than the sum of its proper divisors (14335729).

99861391 is a wasteful number, since it uses less digits than its factorization.

99861391 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8733.

The product of its digits is 104976, while the sum is 46.

The square root of 99861391 is about 9993.0671467773. The cubic root of 99861391 is about 463.9443288712.

The spelling of 99861391 in words is "ninety-nine million, eight hundred sixty-one thousand, three hundred ninety-one".