189612109 has 2 divisors, whose sum is σ = 189612110. Its totient is φ = 189612108.

The previous prime is 189612091. The next prime is 189612113. The reversal of 189612109 is 901216981.

Together with previous prime (189612091) it forms an Ormiston pair, because they use the same digits, order apart.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 177688900 + 11923209 = 13330^2 + 3453^2 .

It is a cyclic number.

It is not a de Polignac number, because 189612109 - 2¹³ = 189603917 is a prime.

It is an alternating number because its digits alternate between odd and even.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (189612139) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 94806054 + 94806055.

It is an arithmetic number, because the mean of its divisors is an integer number (94806055).

Almost surely, 2^189612109 is an apocalyptic number.

It is an amenable number.

189612109 is a deficient number, since it is larger than the sum of its proper divisors (1).

189612109 is an equidigital number, since it uses as much as digits as its factorization.

189612109 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 7776, while the sum is 37.

The square root of 189612109 is about 13769.9712781109. The cubic root of 189612109 is about 574.4982228661.

The spelling of 189612109 in words is "one hundred eighty-nine million, six hundred twelve thousand, one hundred nine".