99999999997 has 4 divisors (see below), whose sum is σ = 105882352956. Its totient is φ = 94117647040.

The previous prime is 99999999977. The next prime is 100000000003. The reversal of 99999999997 is 79999999999.

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 47879566596 + 52120433401 = 218814^2 + 228299^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-99999999997 is a prime.

It is a Duffinian number.

It is a nialpdrome in base 10.

It is a junction number, because it is equal to n+sod(n) for n = 99999999899 and 99999999908.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (99999999907) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2941176454 + ... + 2941176487.

It is an arithmetic number, because the mean of its divisors is an integer number (26470588239).

Almost surely, 2^99999999997 is an apocalyptic number.

It is an amenable number.

99999999997 is a deficient number, since it is larger than the sum of its proper divisors (5882352959).

99999999997 is a wasteful number, since it uses less digits than its factorization.

99999999997 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5882352958.

The product of its digits is 24407490807, while the sum is 97.

The spelling of 99999999997 in words is "ninety-nine billion, nine hundred ninety-nine million, nine hundred ninety-nine thousand, nine hundred ninety-seven".