8557978643 has 4 divisors (see below), whose sum is σ = 8589792960. Its totient is φ = 8526164328.

The previous prime is 8557978633. The next prime is 8557978697. The reversal of 8557978643 is 3468797558.

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

It is a cyclic number.

It is not a de Polignac number, because 8557978643 - 2⁶ = 8557978579 is a prime.

It is a super-3 number, since 3×8557978643³ (a number of 31 digits) contains 333 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (8557978633) 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, 15906755 + ... + 15907292.

It is an arithmetic number, because the mean of its divisors is an integer number (2147448240).

Almost surely, 2^8557978643 is an apocalyptic number.

8557978643 is a deficient number, since it is larger than the sum of its proper divisors (31814317).

8557978643 is a wasteful number, since it uses less digits than its factorization.

8557978643 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 31814316.

The product of its digits is 50803200, while the sum is 62.

The square root of 8557978643 is about 92509.3435443145. The cubic root of 8557978643 is about 2045.4572135443.

The spelling of 8557978643 in words is "eight billion, five hundred fifty-seven million, nine hundred seventy-eight thousand, six hundred forty-three".