78217959 has 8 divisors (see below), whose sum is σ = 107886960. Its totient is φ = 50347136.

The previous prime is 78217943. The next prime is 78217961. The reversal of 78217959 is 95971287.

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 78217959 - 2⁴ = 78217943 is a prime.

It is a super-2 number, since 2×78217959² = 12236098220251362, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78217939) 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, 449442 + ... + 449615.

It is an arithmetic number, because the mean of its divisors is an integer number (13485870).

Almost surely, 2^78217959 is an apocalyptic number.

78217959 is a deficient number, since it is larger than the sum of its proper divisors (29669001).

78217959 is a wasteful number, since it uses less digits than its factorization.

78217959 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 899089.

The product of its digits is 317520, while the sum is 48.

The square root of 78217959 is about 8844.0917566475. The cubic root of 78217959 is about 427.6634742949.

The spelling of 78217959 in words is "seventy-eight million, two hundred seventeen thousand, nine hundred fifty-nine".