78117155 has 8 divisors (see below), whose sum is σ = 96973200. Its totient is φ = 60338656.

The previous prime is 78117133. The next prime is 78117163. The reversal of 78117155 is 55171187.

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 78117155 - 2¹⁰ = 78116131 is a prime.

It is a super-2 number, since 2×78117155² = 12204579810588050, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 269225 + ... + 269514.

It is an arithmetic number, because the mean of its divisors is an integer number (12121650).

Almost surely, 2^78117155 is an apocalyptic number.

78117155 is a deficient number, since it is larger than the sum of its proper divisors (18856045).

78117155 is a wasteful number, since it uses less digits than its factorization.

78117155 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 538773.

The product of its digits is 9800, while the sum is 35.

The square root of 78117155 is about 8838.3909734748. The cubic root of 78117155 is about 427.4796771115.

The spelling of 78117155 in words is "seventy-eight million, one hundred seventeen thousand, one hundred fifty-five".