187221061 has 2 divisors, whose sum is σ = 187221062. Its totient is φ = 187221060.

The previous prime is 187221053. The next prime is 187221113. The reversal of 187221061 is 160122781.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 179828100 + 7392961 = 13410^2 + 2719^2 .

It is a cyclic number.

It is not a de Polignac number, because 187221061 - 2³ = 187221053 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (187221161) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 93610530 + 93610531.

It is an arithmetic number, because the mean of its divisors is an integer number (93610531).

Almost surely, 2^187221061 is an apocalyptic number.

It is an amenable number.

187221061 is a deficient number, since it is larger than the sum of its proper divisors (1).

187221061 is an equidigital number, since it uses as much as digits as its factorization.

187221061 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1344, while the sum is 28.

The square root of 187221061 is about 13682.8747344993. The cubic root of 187221061 is about 572.0731533496.

The spelling of 187221061 in words is "one hundred eighty-seven million, two hundred twenty-one thousand, sixty-one".