1198978877 has 2 divisors, whose sum is σ = 1198978878. Its totient is φ = 1198978876.

The previous prime is 1198978861. The next prime is 1198978889. The reversal of 1198978877 is 7788798911.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 967147801 + 231831076 = 31099^2 + 15226^2 .

It is a cyclic number.

It is not a de Polignac number, because 1198978877 - 2⁴ = 1198978861 is a prime.

It is a super-2 number, since 2×1198978877² = 2875100694984362258, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1198978817) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 599489438 + 599489439.

It is an arithmetic number, because the mean of its divisors is an integer number (599489439).

Almost surely, 2^1198978877 is an apocalyptic number.

It is an amenable number.

1198978877 is a deficient number, since it is larger than the sum of its proper divisors (1).

1198978877 is an equidigital number, since it uses as much as digits as its factorization.

1198978877 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 14224896, while the sum is 65.

The square root of 1198978877 is about 34626.2743736602. The cubic root of 1198978877 is about 1062.3570655613.

The spelling of 1198978877 in words is "one billion, one hundred ninety-eight million, nine hundred seventy-eight thousand, eight hundred seventy-seven".