78864919 has 8 divisors (see below), whose sum is σ = 92049408. Its totient is φ = 66159960.

The previous prime is 78864917. The next prime is 78864931. The reversal of 78864919 is 91946887.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 78864919 - 2¹ = 78864917 is a prime.

It is a super-2 number, since 2×78864919² = 12439350897753122, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78864913) 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 7 ways as a sum of consecutive naturals, for example, 119527 + ... + 120184.

It is an arithmetic number, because the mean of its divisors is an integer number (11506176).

Almost surely, 2^78864919 is an apocalyptic number.

78864919 is a deficient number, since it is larger than the sum of its proper divisors (13184489).

78864919 is a wasteful number, since it uses less digits than its factorization.

78864919 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 239765.

The product of its digits is 870912, while the sum is 52.

The square root of 78864919 is about 8880.5922662849. The cubic root of 78864919 is about 428.8393415692.

The spelling of 78864919 in words is "seventy-eight million, eight hundred sixty-four thousand, nine hundred nineteen".