84129181 has 2 divisors, whose sum is σ = 84129182. Its totient is φ = 84129180.

The previous prime is 84129127. The next prime is 84129211. The reversal of 84129181 is 18192148.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 50893956 + 33235225 = 7134^2 + 5765^2 .

It is a cyclic number.

It is not a de Polignac number, because 84129181 - 2⁷ = 84129053 is a prime.

It is a super-2 number, since 2×84129181² = 14155438191461522, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (84129781) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 42064590 + 42064591.

It is an arithmetic number, because the mean of its divisors is an integer number (42064591).

Almost surely, 2^84129181 is an apocalyptic number.

It is an amenable number.

84129181 is a deficient number, since it is larger than the sum of its proper divisors (1).

84129181 is an equidigital number, since it uses as much as digits as its factorization.

84129181 is an evil number, because the sum of its binary digits is even.

The product of its digits is 4608, while the sum is 34.

The square root of 84129181 is about 9172.1960838177. The cubic root of 84129181 is about 438.1763032319.

The spelling of 84129181 in words is "eighty-four million, one hundred twenty-nine thousand, one hundred eighty-one".