2191659461 has 4 divisors (see below), whose sum is σ = 2200391424. Its totient is φ = 2182927500.

The previous prime is 2191659439. The next prime is 2191659467. The reversal of 2191659461 is 1649561912.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 2191659461 - 2¹⁰ = 2191658437 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 (2191659467) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4365605 + ... + 4366106.

It is an arithmetic number, because the mean of its divisors is an integer number (550097856).

Almost surely, 2^2191659461 is an apocalyptic number.

It is an amenable number.

2191659461 is a deficient number, since it is larger than the sum of its proper divisors (8731963).

2191659461 is an equidigital number, since it uses as much as digits as its factorization.

2191659461 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8731962.

The product of its digits is 116640, while the sum is 44.

The square root of 2191659461 is about 46815.1627253393. The cubic root of 2191659461 is about 1298.9457845815.

The spelling of 2191659461 in words is "two billion, one hundred ninety-one million, six hundred fifty-nine thousand, four hundred sixty-one".