18642421029969 has 45 divisors (see below), whose sum is σ = 30611096904619. Its totient is φ = 11298177926640.

The previous prime is 18642421029919. The next prime is 18642421029977. The reversal of 18642421029969 is 96992012424681.

The square root of 18642421029969 is 4317687.

It is a perfect power (a square), and thus also a powerful number.

18642421029969 is a `hidden beast` number, since 1 + 8 + 64 + 2 + 421 + 0 + 2 + 99 + 69 = 666.

It can be written as a sum of positive squares in only one way, i.e., 14148919865025 + 4493501164944 = 3761505^2 + 2119788^2 .

It is not a de Polignac number, because 18642421029969 - 2¹¹ = 18642421027921 is a prime.

It is a super-2 number, since 2×18642421029969² (a number of 27 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (18642421029919) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 44 ways as a sum of consecutive naturals, for example, 427429207 + ... + 427472819.

Almost surely, 2^{18642421029969} is an apocalyptic number.

18642421029969 is the 4317687-th square number.

18642421029969 is the 2158844-th centered octagonal number.

It is an amenable number.

18642421029969 is a deficient number, since it is larger than the sum of its proper divisors (11968675874650).

18642421029969 is an frugal number, since it uses more digits than its factorization.

18642421029969 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 87260 (or 43627 counting only the distinct ones).

The product of its (nonzero) digits is 26873856, while the sum is 63.

The spelling of 18642421029969 in words is "eighteen trillion, six hundred forty-two billion, four hundred twenty-one million, twenty-nine thousand, nine hundred sixty-nine".