66156749992 has 8 divisors (see below), whose sum is σ = 124043906250. Its totient is φ = 33078374992.

The previous prime is 66156749983. The next prime is 66156750043. The reversal of 66156749992 is 29994765166.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 63971561476 + 2185188516 = 252926^2 + 46746^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is a hoax number, since the sum of its digits (64) coincides with the sum of the digits of its distinct prime factors.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4134796867 + ... + 4134796882.

Almost surely, 2^66156749992 is an apocalyptic number.

It is an amenable number.

66156749992 is a deficient number, since it is larger than the sum of its proper divisors (57887156258).

66156749992 is a wasteful number, since it uses less digits than its factorization.

66156749992 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8269593755 (or 8269593751 counting only the distinct ones).

The product of its digits is 44089920, while the sum is 64.

The spelling of 66156749992 in words is "sixty-six billion, one hundred fifty-six million, seven hundred forty-nine thousand, nine hundred ninety-two".