99879940609 has 8 divisors (see below), whose sum is σ = 100625115240. Its totient is φ = 99137471616.

The previous prime is 99879940543. The next prime is 99879940613. The reversal of 99879940609 is 90604997899.

It can be written as a sum of positive squares in 4 ways, for example, as 9555649009 + 90324291600 = 97753^2 + 300540^2 .

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 99879940609 - 2¹³ = 99879932417 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (99879940649) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 602274 + ... + 749995.

It is an arithmetic number, because the mean of its divisors is an integer number (12578139405).

Almost surely, 2^99879940609 is an apocalyptic number.

It is an amenable number.

99879940609 is a deficient number, since it is larger than the sum of its proper divisors (745174631).

99879940609 is a wasteful number, since it uses less digits than its factorization.

99879940609 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1352819.

The product of its (nonzero) digits is 79361856, while the sum is 70.

The spelling of 99879940609 in words is "ninety-nine billion, eight hundred seventy-nine million, nine hundred forty thousand, six hundred nine".