1178878121 has 2 divisors, whose sum is σ = 1178878122. Its totient is φ = 1178878120.

The previous prime is 1178878109. The next prime is 1178878163. The reversal of 1178878121 is 1218788711.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1175118400 + 3759721 = 34280^2 + 1939^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1178878121 is a prime.

It is not a weakly prime, because it can be changed into another prime (1178871121) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 589439060 + 589439061.

It is an arithmetic number, because the mean of its divisors is an integer number (589439061).

Almost surely, 2^1178878121 is an apocalyptic number.

It is an amenable number.

1178878121 is a deficient number, since it is larger than the sum of its proper divisors (1).

1178878121 is an equidigital number, since it uses as much as digits as its factorization.

1178878121 is an evil number, because the sum of its binary digits is even.

The product of its digits is 50176, while the sum is 44.

The square root of 1178878121 is about 34334.7946112977. The cubic root of 1178878121 is about 1056.3868081096.

The spelling of 1178878121 in words is "one billion, one hundred seventy-eight million, eight hundred seventy-eight thousand, one hundred twenty-one".