329728981 has 2 divisors, whose sum is σ = 329728982. Its totient is φ = 329728980.

The previous prime is 329728969. The next prime is 329729047. The reversal of 329728981 is 189827923.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 308880625 + 20848356 = 17575^2 + 4566^2 .

It is an emirp because it is prime and its reverse (189827923) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 329728981 - 2¹³ = 329720789 is a prime.

It is a super-2 number, since 2×329728981² = 217442401822596722, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (329728901) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 164864490 + 164864491.

It is an arithmetic number, because the mean of its divisors is an integer number (164864491).

Almost surely, 2^329728981 is an apocalyptic number.

It is an amenable number.

329728981 is a deficient number, since it is larger than the sum of its proper divisors (1).

329728981 is an equidigital number, since it uses as much as digits as its factorization.

329728981 is an evil number, because the sum of its binary digits is even.

The product of its digits is 435456, while the sum is 49.

The square root of 329728981 is about 18158.4410399131. The cubic root of 329728981 is about 690.8530938159.

The spelling of 329728981 in words is "three hundred twenty-nine million, seven hundred twenty-eight thousand, nine hundred eighty-one".