180400091 has 2 divisors, whose sum is σ = 180400092. Its totient is φ = 180400090.

The previous prime is 180400081. The next prime is 180400127. The reversal of 180400091 is 190004081.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-180400091 is a prime.

It is not a weakly prime, because it can be changed into another prime (180400081) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 90200045 + 90200046.

It is an arithmetic number, because the mean of its divisors is an integer number (90200046).

Almost surely, 2^180400091 is an apocalyptic number.

180400091 is a deficient number, since it is larger than the sum of its proper divisors (1).

180400091 is an equidigital number, since it uses as much as digits as its factorization.

180400091 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 288, while the sum is 23.

The square root of 180400091 is about 13431.3100999121. The cubic root of 180400091 is about 565.0396411480.

The spelling of 180400091 in words is "one hundred eighty million, four hundred thousand, ninety-one".