61191605 has 8 divisors (see below), whose sum is σ = 73503672. Its totient is φ = 48904128.

The previous prime is 61191589. The next prime is 61191607. The reversal of 61191605 is 50619116.

It can be written as a sum of positive squares in 4 ways, for example, as 14638276 + 46553329 = 3826^2 + 6823^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 61191605 - 2⁴ = 61191589 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61191607) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 134 + ... + 11063.

It is an arithmetic number, because the mean of its divisors is an integer number (9187959).

Almost surely, 2^61191605 is an apocalyptic number.

It is an amenable number.

61191605 is a deficient number, since it is larger than the sum of its proper divisors (12312067).

61191605 is a wasteful number, since it uses less digits than its factorization.

61191605 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12295.

The product of its (nonzero) digits is 1620, while the sum is 29.

The square root of 61191605 is about 7822.5063119182. The cubic root of 61191605 is about 394.0614473808.

The spelling of 61191605 in words is "sixty-one million, one hundred ninety-one thousand, six hundred five".