7166121997 has 4 divisors (see below), whose sum is σ = 7301331900. Its totient is φ = 7030912096.

The previous prime is 7166121943. The next prime is 7166122069. The reversal of 7166121997 is 7991216617.

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 4948559716 + 2217562281 = 70346^2 + 47091^2 .

It is a cyclic number.

It is not a de Polignac number, because 7166121997 - 2¹⁹ = 7165597709 is a prime.

It is a Smith number, since the sum of its digits (49) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 7166121997.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (7166121917) 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, 67604872 + ... + 67604977.

It is an arithmetic number, because the mean of its divisors is an integer number (1825332975).

Almost surely, 2^7166121997 is an apocalyptic number.

It is an amenable number.

7166121997 is a deficient number, since it is larger than the sum of its proper divisors (135209903).

7166121997 is a wasteful number, since it uses less digits than its factorization.

7166121997 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 135209902.

The product of its digits is 285768, while the sum is 49.

The square root of 7166121997 is about 84652.9503148000. The cubic root of 7166121997 is about 1927.9454091917.

The spelling of 7166121997 in words is "seven billion, one hundred sixty-six million, one hundred twenty-one thousand, nine hundred ninety-seven".