61171339391 has 4 divisors (see below), whose sum is σ = 62824618872. Its totient is φ = 59518059912.

The previous prime is 61171339267. The next prime is 61171339421. The reversal of 61171339391 is 19393317116.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-61171339391 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 (61171339991) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 826639685 + ... + 826639758.

It is an arithmetic number, because the mean of its divisors is an integer number (15706154718).

Almost surely, 2^61171339391 is an apocalyptic number.

61171339391 is a deficient number, since it is larger than the sum of its proper divisors (1653279481).

61171339391 is a wasteful number, since it uses less digits than its factorization.

61171339391 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1653279480.

The product of its digits is 91854, while the sum is 44.

The spelling of 61171339391 in words is "sixty-one billion, one hundred seventy-one million, three hundred thirty-nine thousand, three hundred ninety-one".