187089491 has 2 divisors, whose sum is σ = 187089492. Its totient is φ = 187089490.

The previous prime is 187089479. The next prime is 187089559. The reversal of 187089491 is 194980781.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 187089491 - 2¹⁰ = 187088467 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (187089421) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 93544745 + 93544746.

It is an arithmetic number, because the mean of its divisors is an integer number (93544746).

Almost surely, 2^187089491 is an apocalyptic number.

187089491 is a deficient number, since it is larger than the sum of its proper divisors (1).

187089491 is an equidigital number, since it uses as much as digits as its factorization.

187089491 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 145152, while the sum is 47.

The square root of 187089491 is about 13678.0660548193. The cubic root of 187089491 is about 571.9391134028.

The spelling of 187089491 in words is "one hundred eighty-seven million, eighty-nine thousand, four hundred ninety-one".