78555128 has 8 divisors (see below), whose sum is σ = 147290880. Its totient is φ = 39277560.

The previous prime is 78555121. The next prime is 78555133. The reversal of 78555128 is 82155587.

It is a tau number, because it is divible by the number of its divisors (8).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78555121) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4909688 + ... + 4909703.

It is an arithmetic number, because the mean of its divisors is an integer number (18411360).

Almost surely, 2^78555128 is an apocalyptic number.

It is an amenable number.

78555128 is a deficient number, since it is larger than the sum of its proper divisors (68735752).

78555128 is a wasteful number, since it uses less digits than its factorization.

78555128 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9819397 (or 9819393 counting only the distinct ones).

The product of its digits is 112000, while the sum is 41.

The square root of 78555128 is about 8863.1330803503. The cubic root of 78555128 is about 428.2770936909.

The spelling of 78555128 in words is "seventy-eight million, five hundred fifty-five thousand, one hundred twenty-eight".