187240321 has 2 divisors, whose sum is σ = 187240322. Its totient is φ = 187240320.

The previous prime is 187240297. The next prime is 187240331. The reversal of 187240321 is 123042781.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 181306225 + 5934096 = 13465^2 + 2436^2 .

It is a cyclic number.

It is not a de Polignac number, because 187240321 - 2⁵ = 187240289 is a prime.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 187240321.

It is not a weakly prime, because it can be changed into another prime (187240331) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 93620160 + 93620161.

It is an arithmetic number, because the mean of its divisors is an integer number (93620161).

Almost surely, 2^187240321 is an apocalyptic number.

It is an amenable number.

187240321 is a deficient number, since it is larger than the sum of its proper divisors (1).

187240321 is an equidigital number, since it uses as much as digits as its factorization.

187240321 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2688, while the sum is 28.

The square root of 187240321 is about 13683.5785158708. The cubic root of 187240321 is about 572.0927696454.

The spelling of 187240321 in words is "one hundred eighty-seven million, two hundred forty thousand, three hundred twenty-one".