18961529 has 2 divisors, whose sum is σ = 18961530. Its totient is φ = 18961528.

The previous prime is 18961507. The next prime is 18961559. The reversal of 18961529 is 92516981.

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., 17205904 + 1755625 = 4148^2 + 1325^2 .

It is an emirp because it is prime and its reverse (92516981) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-18961529 is a prime.

It is not a weakly prime, because it can be changed into another prime (18961559) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9480764 + 9480765.

It is an arithmetic number, because the mean of its divisors is an integer number (9480765).

Almost surely, 2^18961529 is an apocalyptic number.

It is an amenable number.

18961529 is a deficient number, since it is larger than the sum of its proper divisors (1).

18961529 is an equidigital number, since it uses as much as digits as its factorization.

18961529 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 38880, while the sum is 41.

The square root of 18961529 is about 4354.4837811157. The cubic root of 18961529 is about 266.6599447958.

The spelling of 18961529 in words is "eighteen million, nine hundred sixty-one thousand, five hundred twenty-nine".