77966056978 has 8 divisors (see below), whose sum is σ = 117984033468. Its totient is φ = 38638045824.

The previous prime is 77966056963. The next prime is 77966057021. The reversal of 77966056978 is 87965066977.

It can be written as a sum of positive squares in 2 ways, for example, as 66701843289 + 11264213689 = 258267^2 + 106133^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 172491051 + ... + 172491502.

Almost surely, 2^77966056978 is an apocalyptic number.

77966056978 is a deficient number, since it is larger than the sum of its proper divisors (40017976490).

77966056978 is a wasteful number, since it uses less digits than its factorization.

77966056978 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 344982668.

The product of its (nonzero) digits is 240045120, while the sum is 70.

Subtracting 77966056978 from its reverse (87965066977), we obtain a palindrome (9999009999).

It can be divided in two parts, 779660 and 56978, that added together give a palindrome (836638).

The spelling of 77966056978 in words is "seventy-seven billion, nine hundred sixty-six million, fifty-six thousand, nine hundred seventy-eight".