78119999 has 4 divisors (see below), whose sum is σ = 78242136. Its totient is φ = 77997864.

The previous prime is 78119957. The next prime is 78120011. The reversal of 78119999 is 99991187.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 99991187 = 4969 ⋅20123.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-78119999 is a prime.

It is a super-2 number, since 2×78119999² = 12205468487520002, which contains 22 as substring.

It is a Duffinian number.

78119999 is a modest number, since divided by 9999 gives 7811 as remainder.

It is a self number, because there is not a number n which added to its sum of digits gives 78119999.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78119929) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 60104 + ... + 61389.

It is an arithmetic number, because the mean of its divisors is an integer number (19560534).

Almost surely, 2^78119999 is an apocalyptic number.

78119999 is a deficient number, since it is larger than the sum of its proper divisors (122137).

78119999 is a wasteful number, since it uses less digits than its factorization.

78119999 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 122136.

The product of its digits is 367416, while the sum is 53.

The square root of 78119999 is about 8838.5518610234. The cubic root of 78119999 is about 427.4848647788.

The spelling of 78119999 in words is "seventy-eight million, one hundred nineteen thousand, nine hundred ninety-nine".