61173445687 has 4 divisors (see below), whose sum is σ = 61177268680. Its totient is φ = 61169622696.

The previous prime is 61173445681. The next prime is 61173445699. The reversal of 61173445687 is 78654437116.

It is a happy number.

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 61173445687 - 2³ = 61173445679 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 (61173445681) 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, 1887393 + ... + 1919530.

It is an arithmetic number, because the mean of its divisors is an integer number (15294317170).

Almost surely, 2^61173445687 is an apocalyptic number.

61173445687 is a deficient number, since it is larger than the sum of its proper divisors (3822993).

61173445687 is a wasteful number, since it uses less digits than its factorization.

61173445687 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3822992.

The product of its digits is 3386880, while the sum is 52.

The spelling of 61173445687 in words is "sixty-one billion, one hundred seventy-three million, four hundred forty-five thousand, six hundred eighty-seven".