2116657397 has 4 divisors (see below), whose sum is σ = 2124893676. Its totient is φ = 2108421120.

The previous prime is 2116657357. The next prime is 2116657421. The reversal of 2116657397 is 7937566112.

It is a happy number.

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 1213895281 + 902762116 = 34841^2 + 30046^2 .

It is a cyclic number.

It is not a de Polignac number, because 2116657397 - 2¹⁶ = 2116591861 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2116657337) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4117754 + ... + 4118267.

It is an arithmetic number, because the mean of its divisors is an integer number (531223419).

Almost surely, 2^2116657397 is an apocalyptic number.

It is an amenable number.

2116657397 is a deficient number, since it is larger than the sum of its proper divisors (8236279).

2116657397 is an equidigital number, since it uses as much as digits as its factorization.

2116657397 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8236278.

The product of its digits is 476280, while the sum is 47.

The square root of 2116657397 is about 46007.1450646527. The cubic root of 2116657397 is about 1283.9561431839.

The spelling of 2116657397 in words is "two billion, one hundred sixteen million, six hundred fifty-seven thousand, three hundred ninety-seven".