66845510837 has 4 divisors (see below), whose sum is σ = 76394869536. Its totient is φ = 57296152140.

The previous prime is 66845510827. The next prime is 66845510863. The reversal of 66845510837 is 73801554866.

66845510837 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 a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 66845510837 - 2²⁶ = 66778401973 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66845510827) 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, 4774679339 + ... + 4774679352.

It is an arithmetic number, because the mean of its divisors is an integer number (19098717384).

Almost surely, 2^66845510837 is an apocalyptic number.

It is an amenable number.

66845510837 is a deficient number, since it is larger than the sum of its proper divisors (9549358699).

66845510837 is an equidigital number, since it uses as much as digits as its factorization.

66845510837 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9549358698.

The product of its (nonzero) digits is 4838400, while the sum is 53.

The spelling of 66845510837 in words is "sixty-six billion, eight hundred forty-five million, five hundred ten thousand, eight hundred thirty-seven".