7978547689129 has 2 divisors, whose sum is σ = 7978547689130. Its totient is φ = 7978547689128.

The previous prime is 7978547689127. The next prime is 7978547689141. The reversal of 7978547689129 is 9219867458797.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 6627931823529 + 1350615865600 = 2574477^2 + 1162160^2 .

It is a cyclic number.

It is not a de Polignac number, because 7978547689129 - 2¹ = 7978547689127 is a prime.

Together with 7978547689127, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (7978547689121) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3989273844564 + 3989273844565.

It is an arithmetic number, because the mean of its divisors is an integer number (3989273844565).

Almost surely, 2^{7978547689129} is an apocalyptic number.

It is an amenable number.

7978547689129 is a deficient number, since it is larger than the sum of its proper divisors (1).

7978547689129 is an equidigital number, since it uses as much as digits as its factorization.

7978547689129 is an evil number, because the sum of its binary digits is even.

The product of its digits is 3840721920, while the sum is 82.

The spelling of 7978547689129 in words is "seven trillion, nine hundred seventy-eight billion, five hundred forty-seven million, six hundred eighty-nine thousand, one hundred twenty-nine".