5561177891 has 2 divisors, whose sum is σ = 5561177892. Its totient is φ = 5561177890.

The previous prime is 5561177861. The next prime is 5561177893. The reversal of 5561177891 is 1987711655.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 5561177891 - 2²² = 5556983587 is a prime.

Together with 5561177893, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (5561177893) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2780588945 + 2780588946.

It is an arithmetic number, because the mean of its divisors is an integer number (2780588946).

Almost surely, 2^5561177891 is an apocalyptic number.

5561177891 is a deficient number, since it is larger than the sum of its proper divisors (1).

5561177891 is an equidigital number, since it uses as much as digits as its factorization.

5561177891 is an evil number, because the sum of its binary digits is even.

The product of its digits is 529200, while the sum is 50.

The square root of 5561177891 is about 74573.3054852740. The cubic root of 5561177891 is about 1771.6948761635.

The spelling of 5561177891 in words is "five billion, five hundred sixty-one million, one hundred seventy-seven thousand, eight hundred ninety-one".