4191918087661 has 4 divisors (see below), whose sum is σ = 4191962949052. Its totient is φ = 4191873226272.

The previous prime is 4191918087653. The next prime is 4191918087673. The reversal of 4191918087661 is 1667808191914.

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 3510807901225 + 681110186436 = 1873715^2 + 825294^2 .

It is a cyclic number.

It is not a de Polignac number, because 4191918087661 - 2³ = 4191918087653 is a prime.

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 4191918087661.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (4191918087961) 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, 22290240 + ... + 22477513.

It is an arithmetic number, because the mean of its divisors is an integer number (1047990737263).

Almost surely, 2^{4191918087661} is an apocalyptic number.

It is an amenable number.

4191918087661 is a deficient number, since it is larger than the sum of its proper divisors (44861391).

4191918087661 is an equidigital number, since it uses as much as digits as its factorization.

4191918087661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 44861390.

The product of its (nonzero) digits is 5225472, while the sum is 61.

The spelling of 4191918087661 in words is "four trillion, one hundred ninety-one billion, nine hundred eighteen million, eighty-seven thousand, six hundred sixty-one".