66755737641 has 4 divisors (see below), whose sum is σ = 89007650192. Its totient is φ = 44503825092.

The previous prime is 66755737639. The next prime is 66755737651. The reversal of 66755737641 is 14673755766.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 66755737641 - 2¹ = 66755737639 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (66755737651) 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, 11125956271 + ... + 11125956276.

It is an arithmetic number, because the mean of its divisors is an integer number (22251912548).

Almost surely, 2^66755737641 is an apocalyptic number.

It is an amenable number.

66755737641 is a deficient number, since it is larger than the sum of its proper divisors (22251912551).

66755737641 is a wasteful number, since it uses less digits than its factorization.

66755737641 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22251912550.

The product of its digits is 22226400, while the sum is 57.

The spelling of 66755737641 in words is "sixty-six billion, seven hundred fifty-five million, seven hundred thirty-seven thousand, six hundred forty-one".