29940840581 has 2 divisors, whose sum is σ = 29940840582. Its totient is φ = 29940840580.

The previous prime is 29940840551. The next prime is 29940840593. The reversal of 29940840581 is 18504804992.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 18134931556 + 11805909025 = 134666^2 + 108655^2 .

It is a cyclic number.

It is not a de Polignac number, because 29940840581 - 2¹⁰ = 29940839557 is a prime.

It is a super-2 number, since 2×29940840581² (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 (29940840551) 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, 14970420290 + 14970420291.

It is an arithmetic number, because the mean of its divisors is an integer number (14970420291).

Almost surely, 2^29940840581 is an apocalyptic number.

It is an amenable number.

29940840581 is a deficient number, since it is larger than the sum of its proper divisors (1).

29940840581 is an equidigital number, since it uses as much as digits as its factorization.

29940840581 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 829440, while the sum is 50.

The spelling of 29940840581 in words is "twenty-nine billion, nine hundred forty million, eight hundred forty thousand, five hundred eighty-one".