42780617729 has 2 divisors, whose sum is σ = 42780617730. Its totient is φ = 42780617728.

The previous prime is 42780617701. The next prime is 42780617749. The reversal of 42780617729 is 92771608724.

42780617729 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 40632480625 + 2148137104 = 201575^2 + 46348^2 .

It is a cyclic number.

It is not a de Polignac number, because 42780617729 - 2²⁴ = 42763840513 is a prime.

It is not a weakly prime, because it can be changed into another prime (42780617749) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 21390308864 + 21390308865.

It is an arithmetic number, because the mean of its divisors is an integer number (21390308865).

Almost surely, 2^42780617729 is an apocalyptic number.

It is an amenable number.

42780617729 is a deficient number, since it is larger than the sum of its proper divisors (1).

42780617729 is an equidigital number, since it uses as much as digits as its factorization.

42780617729 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2370816, while the sum is 53.

The spelling of 42780617729 in words is "forty-two billion, seven hundred eighty million, six hundred seventeen thousand, seven hundred twenty-nine".