6191661 has 16 divisors (see below), whose sum is σ = 9740288. Its totient is φ = 3423600.

The previous prime is 6191659. The next prime is 6191677. The reversal of 6191661 is 1661916.

It is a happy number.

6191661 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 6191661 - 2¹ = 6191659 is a prime.

It is a Smith number, since the sum of its digits (30) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is an Ulam number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6191611) 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, 4105 + ... + 5406.

It is an arithmetic number, because the mean of its divisors is an integer number (608768).

Almost surely, 2^6191661 is an apocalyptic number.

It is an amenable number.

6191661 is a deficient number, since it is larger than the sum of its proper divisors (3548627).

6191661 is a wasteful number, since it uses less digits than its factorization.

6191661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9552.

The product of its digits is 1944, while the sum is 30.

The square root of 6191661 is about 2488.3048446684. The cubic root of 6191661 is about 183.6266551548.

The spelling of 6191661 in words is "six million, one hundred ninety-one thousand, six hundred sixty-one".