187421593 has 2 divisors, whose sum is σ = 187421594. Its totient is φ = 187421592.

The previous prime is 187421543. The next prime is 187421599. The reversal of 187421593 is 395124781.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 104101209 + 83320384 = 10203^2 + 9128^2 .

It is an emirp because it is prime and its reverse (395124781) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-187421593 is a prime.

It is not a weakly prime, because it can be changed into another prime (187421599) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 93710796 + 93710797.

It is an arithmetic number, because the mean of its divisors is an integer number (93710797).

Almost surely, 2^187421593 is an apocalyptic number.

It is an amenable number.

187421593 is a deficient number, since it is larger than the sum of its proper divisors (1).

187421593 is an equidigital number, since it uses as much as digits as its factorization.

187421593 is an evil number, because the sum of its binary digits is even.

The product of its digits is 60480, while the sum is 40.

The square root of 187421593 is about 13690.2006194212. The cubic root of 187421593 is about 572.2773291671.

The spelling of 187421593 in words is "one hundred eighty-seven million, four hundred twenty-one thousand, five hundred ninety-three".