99999642 has 8 divisors (see below), whose sum is σ = 199999296. Its totient is φ = 33333212.

The previous prime is 99999623. The next prime is 99999643. The reversal of 99999642 is 24699999.

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

99999642 is an admirable number.

It is a nialpdrome in base 10.

It is not an unprimeable number, because it can be changed into a prime (99999643) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8333298 + ... + 8333309.

It is an arithmetic number, because the mean of its divisors is an integer number (24999912).

Almost surely, 2^99999642 is an apocalyptic number.

99999642 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

99999642 is a wasteful number, since it uses less digits than its factorization.

99999642 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16666612.

The product of its digits is 2834352, while the sum is 57.

The square root of 99999642 is about 9999.9820999840. The cubic root of 99999642 is about 464.1583294643.

The spelling of 99999642 in words is "ninety-nine million, nine hundred ninety-nine thousand, six hundred forty-two".