32399999981 has 2 divisors, whose sum is σ = 32399999982. Its totient is φ = 32399999980.

The previous prime is 32399999977. The next prime is 32400000089. The reversal of 32399999981 is 18999999323.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 28053235081 + 4346764900 = 167491^2 + 65930^2 .

It is a cyclic number.

It is not a de Polignac number, because 32399999981 - 2² = 32399999977 is a prime.

It is a super-2 number, since 2×32399999981² (a number of 22 digits) contains 22 as substring.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (32399999381) 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 as a sum of consecutive naturals, namely, 16199999990 + 16199999991.

It is an arithmetic number, because the mean of its divisors is an integer number (16199999991).

Almost surely, 2^32399999981 is an apocalyptic number.

It is an amenable number.

32399999981 is a deficient number, since it is larger than the sum of its proper divisors (1).

32399999981 is an equidigital number, since it uses as much as digits as its factorization.

32399999981 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 76527504, while the sum is 71.

The spelling of 32399999981 in words is "thirty-two billion, three hundred ninety-nine million, nine hundred ninety-nine thousand, nine hundred eighty-one".