78455221928 has 16 divisors (see below), whose sum is σ = 147174058080. Its totient is φ = 39208806448.

The previous prime is 78455221921. The next prime is 78455221951. The reversal of 78455221928 is 82912255487.

It is a self number, because there is not a number n which added to its sum of digits gives 78455221928.

It is not an unprimeable number, because it can be changed into a prime (78455221921) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2332826 + ... + 2366217.

It is an arithmetic number, because the mean of its divisors is an integer number (9198378630).

Almost surely, 2^78455221928 is an apocalyptic number.

It is an amenable number.

78455221928 is a deficient number, since it is larger than the sum of its proper divisors (68718836152).

78455221928 is a wasteful number, since it uses less digits than its factorization.

78455221928 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4701136 (or 4701132 counting only the distinct ones).

The product of its digits is 3225600, while the sum is 53.

The spelling of 78455221928 in words is "seventy-eight billion, four hundred fifty-five million, two hundred twenty-one thousand, nine hundred twenty-eight".