78198129 has 24 divisors (see below), whose sum is σ = 123308640. Its totient is φ = 49385376.

The previous prime is 78198121. The next prime is 78198149. The reversal of 78198129 is 92189187.

It is not a de Polignac number, because 78198129 - 2³ = 78198121 is a prime.

It is a super-2 number, since 2×78198129² = 12229894758201282, which contains 22 as substring.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (78198121) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 3852 + ... + 13085.

It is an arithmetic number, because the mean of its divisors is an integer number (5137860).

Almost surely, 2^78198129 is an apocalyptic number.

It is an amenable number.

78198129 is a deficient number, since it is larger than the sum of its proper divisors (45110511).

78198129 is a wasteful number, since it uses less digits than its factorization.

78198129 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16971 (or 16959 counting only the distinct ones).

The product of its digits is 72576, while the sum is 45.

The square root of 78198129 is about 8842.9705981644. The cubic root of 78198129 is about 427.6273304920.

The spelling of 78198129 in words is "seventy-eight million, one hundred ninety-eight thousand, one hundred twenty-nine".