78278866317478 has 8 divisors (see below), whose sum is σ = 117499221809640. Its totient is φ = 39112459047600.

The previous prime is 78278866317409. The next prime is 78278866317493. The reversal of 78278866317478 is 87471366887287.

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

It is a super-2 number, since 2×78278866317478² (a number of 29 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 13487051943 + ... + 13487057746.

It is an arithmetic number, because the mean of its divisors is an integer number (14687402726205).

Almost surely, 2^{78278866317478} is an apocalyptic number.

78278866317478 is a deficient number, since it is larger than the sum of its proper divisors (39220355492162).

78278866317478 is a wasteful number, since it uses less digits than its factorization.

78278866317478 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 26974111142.

The product of its digits is 8497004544, while the sum is 82.

The spelling of 78278866317478 in words is "seventy-eight trillion, two hundred seventy-eight billion, eight hundred sixty-six million, three hundred seventeen thousand, four hundred seventy-eight".