30983989781 has 2 divisors, whose sum is σ = 30983989782. Its totient is φ = 30983989780.

The previous prime is 30983989717. The next prime is 30983989807. The reversal of 30983989781 is 18798938903.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 28092776881 + 2891212900 = 167609^2 + 53770^2 .

It is a cyclic number.

It is not a de Polignac number, because 30983989781 - 2⁶ = 30983989717 is a prime.

It is a super-2 number, since 2×30983989781² (a number of 22 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (30983989381) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15491994890 + 15491994891.

It is an arithmetic number, because the mean of its divisors is an integer number (15491994891).

Almost surely, 2^30983989781 is an apocalyptic number.

It is an amenable number.

30983989781 is a deficient number, since it is larger than the sum of its proper divisors (1).

30983989781 is an equidigital number, since it uses as much as digits as its factorization.

30983989781 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 23514624, while the sum is 65.

The spelling of 30983989781 in words is "thirty billion, nine hundred eighty-three million, nine hundred eighty-nine thousand, seven hundred eighty-one".