181501013 has 2 divisors, whose sum is σ = 181501014. Its totient is φ = 181501012.

The previous prime is 181501009. The next prime is 181501031. The reversal of 181501013 is 310105181.

Together with next prime (181501031) it forms an Ormiston pair, because they use the same digits, order apart.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 175774564 + 5726449 = 13258^2 + 2393^2 .

It is a cyclic number.

It is not a de Polignac number, because 181501013 - 2² = 181501009 is a prime.

It is equal to p_10109072 and since 181501013 and 10109072 have the same sum of digits, it is a Honaker prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (181501213) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 90750506 + 90750507.

It is an arithmetic number, because the mean of its divisors is an integer number (90750507).

Almost surely, 2^181501013 is an apocalyptic number.

It is an amenable number.

181501013 is a deficient number, since it is larger than the sum of its proper divisors (1).

181501013 is an equidigital number, since it uses as much as digits as its factorization.

181501013 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 120, while the sum is 20.

The square root of 181501013 is about 13472.2311812112. The cubic root of 181501013 is about 566.1867274627.

Adding to 181501013 its reverse (310105181), we get a palindrome (491606194).

The spelling of 181501013 in words is "one hundred eighty-one million, five hundred one thousand, thirteen".