8557256978 has 4 divisors (see below), whose sum is σ = 12835885470. Its totient is φ = 4278628488.

The previous prime is 8557256971. The next prime is 8557257047. The reversal of 8557256978 is 8796527558.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 8524274929 + 32982049 = 92327^2 + 5743^2 .

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 8557256978.

It is not an unprimeable number, because it can be changed into a prime (8557256971) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2139314243 + ... + 2139314246.

Almost surely, 2^8557256978 is an apocalyptic number.

8557256978 is a deficient number, since it is larger than the sum of its proper divisors (4278628492).

8557256978 is a wasteful number, since it uses less digits than its factorization.

8557256978 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4278628491.

The product of its digits is 42336000, while the sum is 62.

The square root of 8557256978 is about 92505.4429641845. The cubic root of 8557256978 is about 2045.3997164633.

The spelling of 8557256978 in words is "eight billion, five hundred fifty-seven million, two hundred fifty-six thousand, nine hundred seventy-eight".