1881616291 has 2 divisors, whose sum is σ = 1881616292. Its totient is φ = 1881616290.

The previous prime is 1881616279. The next prime is 1881616313. The reversal of 1881616291 is 1926161881.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 1881616291 - 2⁹ = 1881615779 is a prime.

It is not a weakly prime, because it can be changed into another prime (1881616211) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 940808145 + 940808146.

It is an arithmetic number, because the mean of its divisors is an integer number (940808146).

Almost surely, 2^1881616291 is an apocalyptic number.

1881616291 is a deficient number, since it is larger than the sum of its proper divisors (1).

1881616291 is an equidigital number, since it uses as much as digits as its factorization.

1881616291 is an evil number, because the sum of its binary digits is even.

The product of its digits is 41472, while the sum is 43.

The square root of 1881616291 is about 43377.6012591752. The cubic root of 1881616291 is about 1234.5547501913.

The spelling of 1881616291 in words is "one billion, eight hundred eighty-one million, six hundred sixteen thousand, two hundred ninety-one".