97999999991807 has 16 divisors (see below), whose sum is σ = 105723449298720. Its totient is φ = 90494219092992.

The previous prime is 97999999991687. The next prime is 97999999991813. The reversal of 97999999991807 is 70819999999979.

It is a cyclic number.

It is not a de Polignac number, because 97999999991807 - 2¹⁸ = 97999999729663 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (97999999991857) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 120408608 + ... + 121219770.

It is an arithmetic number, because the mean of its divisors is an integer number (6607715581170).

Almost surely, 2^{97999999991807} is an apocalyptic number.

97999999991807 is a deficient number, since it is larger than the sum of its proper divisors (7723449306913).

97999999991807 is a wasteful number, since it uses less digits than its factorization.

97999999991807 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 945322.

The product of its (nonzero) digits is 151868831688, while the sum is 104.

The spelling of 97999999991807 in words is "ninety-seven trillion, nine hundred ninety-nine billion, nine hundred ninety-nine million, nine hundred ninety-one thousand, eight hundred seven".