1978617928 has 32 divisors (see below), whose sum is σ = 4241784960. Its totient is φ = 847601280.

The previous prime is 1978617863. The next prime is 1978617929. The reversal of 1978617928 is 8297168791.

It is not an unprimeable number, because it can be changed into a prime (1978617929) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 145300 + ... + 158332.

It is an arithmetic number, because the mean of its divisors is an integer number (132555780).

Almost surely, 2^1978617928 is an apocalyptic number.

It is an amenable number.

1978617928 is an abundant number, since it is smaller than the sum of its proper divisors (2263167032).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1978617928 is a wasteful number, since it uses less digits than its factorization.

1978617928 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15757 (or 15753 counting only the distinct ones).

The product of its digits is 3048192, while the sum is 58.

The square root of 1978617928 is about 44481.6583323958. The cubic root of 1978617928 is about 1255.4149996566.

The spelling of 1978617928 in words is "one billion, nine hundred seventy-eight million, six hundred seventeen thousand, nine hundred twenty-eight".