18987999529 has 4 divisors (see below), whose sum is σ = 18988953984. Its totient is φ = 18987045076.

The previous prime is 18987999463. The next prime is 18987999599. The reversal of 18987999529 is 92599978981.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 18987999529 - 2¹⁵ = 18987966761 is a prime.

It is a super-2 number, since 2×18987999529² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18987999599) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 446737 + ... + 487390.

It is an arithmetic number, because the mean of its divisors is an integer number (4747238496).

Almost surely, 2^18987999529 is an apocalyptic number.

It is an amenable number.

18987999529 is a deficient number, since it is larger than the sum of its proper divisors (954455).

18987999529 is an equidigital number, since it uses as much as digits as its factorization.

18987999529 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 954454.

The product of its digits is 264539520, while the sum is 76.

The spelling of 18987999529 in words is "eighteen billion, nine hundred eighty-seven million, nine hundred ninety-nine thousand, five hundred twenty-nine".