78423643985558 has 32 divisors (see below), whose sum is σ = 122959728359424. Its totient is φ = 37442944500192.

The previous prime is 78423643985551. The next prime is 78423643985651. The reversal of 78423643985558 is 85558934632487.

It is a happy number.

It is a super-3 number, since 3×78423643985558³ (a number of 43 digits) contains 333 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78423643985551) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 65551916 + ... + 66737552.

It is an arithmetic number, because the mean of its divisors is an integer number (3842491511232).

Almost surely, 2^{78423643985558} is an apocalyptic number.

78423643985558 is a deficient number, since it is larger than the sum of its proper divisors (44536084373866).

78423643985558 is a wasteful number, since it uses less digits than its factorization.

78423643985558 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1188116.

The product of its digits is 6967296000, while the sum is 77.

The spelling of 78423643985558 in words is "seventy-eight trillion, four hundred twenty-three billion, six hundred forty-three million, nine hundred eighty-five thousand, five hundred fifty-eight".