981581329 has 4 divisors (see below), whose sum is σ = 981745776. Its totient is φ = 981416884.

The previous prime is 981581291. The next prime is 981581333. The reversal of 981581329 is 923185189.

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 981581329 - 2¹¹ = 981579281 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (981581929) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 72919 + ... + 85324.

It is an arithmetic number, because the mean of its divisors is an integer number (245436444).

Almost surely, 2^981581329 is an apocalyptic number.

It is an amenable number.

981581329 is a deficient number, since it is larger than the sum of its proper divisors (164447).

981581329 is a wasteful number, since it uses less digits than its factorization.

981581329 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 164446.

The product of its digits is 155520, while the sum is 46.

The square root of 981581329 is about 31330.1983555802. The cubic root of 981581329 is about 993.8223583297.

The spelling of 981581329 in words is "nine hundred eighty-one million, five hundred eighty-one thousand, three hundred twenty-nine".