66738152081 has 8 divisors (see below), whose sum is σ = 69043599720. Its totient is φ = 64432979968.

The previous prime is 66738152071. The next prime is 66738152123. The reversal of 66738152081 is 18025183766.

It can be written as a sum of positive squares in 4 ways, for example, as 9061326481 + 57676825600 = 95191^2 + 240160^2 .

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

It is a cyclic number.

It is not a de Polignac number, because 66738152081 - 2²² = 66733957777 is a prime.

It is a super-2 number, since 2×66738152081² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66738152071) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 505115 + ... + 623391.

It is an arithmetic number, because the mean of its divisors is an integer number (8630449965).

Almost surely, 2^66738152081 is an apocalyptic number.

It is an amenable number.

66738152081 is a deficient number, since it is larger than the sum of its proper divisors (2305447639).

66738152081 is a wasteful number, since it uses less digits than its factorization.

66738152081 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 137763.

The product of its (nonzero) digits is 483840, while the sum is 47.

The spelling of 66738152081 in words is "sixty-six billion, seven hundred thirty-eight million, one hundred fifty-two thousand, eighty-one".