66603738826 has 4 divisors (see below), whose sum is σ = 99905608242. Its totient is φ = 33301869412.

The previous prime is 66603738787. The next prime is 66603738827. The reversal of 66603738826 is 62883730666.

66603738826 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 62883730666 = 2 ⋅31441865333.

It can be written as a sum of positive squares in only one way, i.e., 61105368025 + 5498370801 = 247195^2 + 74151^2 .

It is not an unprimeable number, because it can be changed into a prime (66603738827) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 16650934705 + ... + 16650934708.

Almost surely, 2^66603738826 is an apocalyptic number.

66603738826 is a deficient number, since it is larger than the sum of its proper divisors (33301869416).

66603738826 is a wasteful number, since it uses less digits than its factorization.

66603738826 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 33301869415.

The product of its (nonzero) digits is 10450944, while the sum is 55.

The spelling of 66603738826 in words is "sixty-six billion, six hundred three million, seven hundred thirty-eight thousand, eight hundred twenty-six".