181138129 has 2 divisors, whose sum is σ = 181138130. Its totient is φ = 181138128.

The previous prime is 181138109. The next prime is 181138159. The reversal of 181138129 is 921831181.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 117505600 + 63632529 = 10840^2 + 7977^2 .

It is a cyclic number.

It is not a de Polignac number, because 181138129 - 2¹³ = 181129937 is a prime.

It is a super-2 number, since 2×181138129² = 65622043555241282, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 181138094 and 181138103.

It is not a weakly prime, because it can be changed into another prime (181138109) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 90569064 + 90569065.

It is an arithmetic number, because the mean of its divisors is an integer number (90569065).

Almost surely, 2^181138129 is an apocalyptic number.

It is an amenable number.

181138129 is a deficient number, since it is larger than the sum of its proper divisors (1).

181138129 is an equidigital number, since it uses as much as digits as its factorization.

181138129 is an evil number, because the sum of its binary digits is even.

The product of its digits is 3456, while the sum is 34.

The square root of 181138129 is about 13458.7565918996. The cubic root of 181138129 is about 565.8091406158.

The spelling of 181138129 in words is "one hundred eighty-one million, one hundred thirty-eight thousand, one hundred twenty-nine".