78820558 has 4 divisors (see below), whose sum is σ = 118230840. Its totient is φ = 39410278.

The previous prime is 78820541. The next prime is 78820583. The reversal of 78820558 is 85502887.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 85502887 = 1621 ⋅52747.

It is a super-3 number, since 3×78820558³ (a number of 25 digits) contains 333 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 19705138 + ... + 19705141.

It is an arithmetic number, because the mean of its divisors is an integer number (29557710).

Almost surely, 2^78820558 is an apocalyptic number.

78820558 is a deficient number, since it is larger than the sum of its proper divisors (39410282).

78820558 is a wasteful number, since it uses less digits than its factorization.

78820558 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 39410281.

The product of its (nonzero) digits is 179200, while the sum is 43.

The square root of 78820558 is about 8878.0942774900. The cubic root of 78820558 is about 428.7589200489.

The spelling of 78820558 in words is "seventy-eight million, eight hundred twenty thousand, five hundred fifty-eight".