66151066778 has 8 divisors (see below), whose sum is σ = 99417055860. Its totient is φ = 33012048160.

The previous prime is 66151066777. The next prime is 66151066799. The reversal of 66151066778 is 87766015166.

It can be written as a sum of positive squares in 2 ways, for example, as 63848698489 + 2302368289 = 252683^2 + 47983^2 .

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

It is not an unprimeable number, because it can be changed into a prime (66151066777) 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, 31741313 + ... + 31743396.

Almost surely, 2^66151066778 is an apocalyptic number.

66151066778 is a deficient number, since it is larger than the sum of its proper divisors (33265989082).

66151066778 is a wasteful number, since it uses less digits than its factorization.

66151066778 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 63485232.

The product of its (nonzero) digits is 2540160, while the sum is 53.

The spelling of 66151066778 in words is "sixty-six billion, one hundred fifty-one million, sixty-six thousand, seven hundred seventy-eight".