8991401329 has 3 divisors (see below), whose sum is σ = 8991496153. Its totient is φ = 8991306506.

The previous prime is 8991401297. The next prime is 8991401359. The reversal of 8991401329 is 9231041998.

It is a happy number.

The square root of 8991401329 is 94823.

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

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is not a de Polignac number, because 8991401329 - 2⁵ = 8991401297 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (8991401359) by changing a digit.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 47412 + ... + 142234.

Almost surely, 2^8991401329 is an apocalyptic number.

8991401329 is the 94823-rd square number.

8991401329 is the 47412-nd centered octagonal number.

It is an amenable number.

8991401329 is a deficient number, since it is larger than the sum of its proper divisors (94824).

8991401329 is an frugal number, since it uses more digits than its factorization.

8991401329 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 189646 (or 94823 counting only the distinct ones).

The product of its (nonzero) digits is 139968, while the sum is 46.

The cubic root of 8991401329 is about 2079.4211691408.

The spelling of 8991401329 in words is "eight billion, nine hundred ninety-one million, four hundred one thousand, three hundred twenty-nine".