867856978 has 32 divisors (see below), whose sum is σ = 1359532080. Its totient is φ = 415134720.

The previous prime is 867856973. The next prime is 867856993. The reversal of 867856978 is 879658768.

It can be written as a sum of positive squares in 8 ways, for example, as 15976009 + 851880969 = 3997^2 + 29187^2 .

It is not an unprimeable number, because it can be changed into a prime (867856973) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2061208 + ... + 2061628.

Almost surely, 2^867856978 is an apocalyptic number.

867856978 is a deficient number, since it is larger than the sum of its proper divisors (491675102).

867856978 is a wasteful number, since it uses less digits than its factorization.

867856978 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 862.

The product of its digits is 40642560, while the sum is 64.

The square root of 867856978 is about 29459.4123838206. The cubic root of 867856978 is about 953.8557892557.

It can be divided in two parts, 8678 and 56978, that added together give a palindrome (65656).

The spelling of 867856978 in words is "eight hundred sixty-seven million, eight hundred fifty-six thousand, nine hundred seventy-eight".