66319434978 has 16 divisors (see below), whose sum is σ = 140441156640. Its totient is φ = 20806097216.

The previous prime is 66319434949. The next prime is 66319434997. The reversal of 66319434978 is 87943491366.

66319434978 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 325095168 + ... + 325095371.

It is an arithmetic number, because the mean of its divisors is an integer number (8777572290).

Almost surely, 2^66319434978 is an apocalyptic number.

66319434978 is an abundant number, since it is smaller than the sum of its proper divisors (74121721662).

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

66319434978 is a wasteful number, since it uses less digits than its factorization.

66319434978 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 650190561.

The product of its digits is 23514624, while the sum is 60.

The spelling of 66319434978 in words is "sixty-six billion, three hundred nineteen million, four hundred thirty-four thousand, nine hundred seventy-eight".