61366191 has 4 divisors (see below), whose sum is σ = 81821592. Its totient is φ = 40910792.

The previous prime is 61366189. The next prime is 61366247. The reversal of 61366191 is 19166316.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 61366191 - 2¹ = 61366189 is a prime.

It is a super-3 number, since 3×61366191³ (a number of 24 digits) contains 333 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61361191) 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, 10227696 + ... + 10227701.

It is an arithmetic number, because the mean of its divisors is an integer number (20455398).

Almost surely, 2^61366191 is an apocalyptic number.

61366191 is a deficient number, since it is larger than the sum of its proper divisors (20455401).

61366191 is a wasteful number, since it uses less digits than its factorization.

61366191 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20455400.

The product of its digits is 5832, while the sum is 33.

The square root of 61366191 is about 7833.6575748497. The cubic root of 61366191 is about 394.4358575985.

The spelling of 61366191 in words is "sixty-one million, three hundred sixty-six thousand, one hundred ninety-one".