188128231 has 2 divisors, whose sum is σ = 188128232. Its totient is φ = 188128230.

The previous prime is 188128207. The next prime is 188128277. The reversal of 188128231 is 132821881.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 188128231 - 2¹⁹ = 187603943 is a prime.

It is a super-2 number, since 2×188128231² = 70784462598378722, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (188128531) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 94064115 + 94064116.

It is an arithmetic number, because the mean of its divisors is an integer number (94064116).

Almost surely, 2^188128231 is an apocalyptic number.

188128231 is a deficient number, since it is larger than the sum of its proper divisors (1).

188128231 is an equidigital number, since it uses as much as digits as its factorization.

188128231 is an evil number, because the sum of its binary digits is even.

The product of its digits is 6144, while the sum is 34.

The square root of 188128231 is about 13715.9845071362. The cubic root of 188128231 is about 572.9956486405.

The spelling of 188128231 in words is "one hundred eighty-eight million, one hundred twenty-eight thousand, two hundred thirty-one".