78998089 has 4 divisors (see below), whose sum is σ = 79016580. Its totient is φ = 78979600.

The previous prime is 78998081. The next prime is 78998107. The reversal of 78998089 is 98089987.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 98089987 = 47 ⋅2087021.

It can be written as a sum of positive squares in 2 ways, for example, as 13630864 + 65367225 = 3692^2 + 8085^2 .

It is a cyclic number.

It is not a de Polignac number, because 78998089 - 2³ = 78998081 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (78998081) 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 3 ways as a sum of consecutive naturals, for example, 807 + ... + 12595.

It is an arithmetic number, because the mean of its divisors is an integer number (19754145).

Almost surely, 2^78998089 is an apocalyptic number.

It is an amenable number.

78998089 is a deficient number, since it is larger than the sum of its proper divisors (18491).

78998089 is a wasteful number, since it uses less digits than its factorization.

78998089 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18490.

The product of its (nonzero) digits is 2612736, while the sum is 58.

The square root of 78998089 is about 8888.0869145165. The cubic root of 78998089 is about 429.0805828452.

The spelling of 78998089 in words is "seventy-eight million, nine hundred ninety-eight thousand, eighty-nine".