187321397 has 2 divisors, whose sum is σ = 187321398. Its totient is φ = 187321396.

The previous prime is 187321349. The next prime is 187321441. The reversal of 187321397 is 793123781.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 167598916 + 19722481 = 12946^2 + 4441^2 .

It is a cyclic number.

It is not a de Polignac number, because 187321397 - 2¹² = 187317301 is a prime.

It is a super-3 number, since 3×187321397³ (a number of 26 digits) contains 333 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (187321097) 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, 93660698 + 93660699.

It is an arithmetic number, because the mean of its divisors is an integer number (93660699).

Almost surely, 2^187321397 is an apocalyptic number.

It is an amenable number.

187321397 is a deficient number, since it is larger than the sum of its proper divisors (1).

187321397 is an equidigital number, since it uses as much as digits as its factorization.

187321397 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 63504, while the sum is 41.

The square root of 187321397 is about 13686.5407243759. The cubic root of 187321397 is about 572.1753307449.

The spelling of 187321397 in words is "one hundred eighty-seven million, three hundred twenty-one thousand, three hundred ninety-seven".