66550406423 has 4 divisors (see below), whose sum is σ = 66974294520. Its totient is φ = 66126518328.

The previous prime is 66550406401. The next prime is 66550406431. The reversal of 66550406423 is 32460405566.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 66550406423 - 2¹⁰ = 66550405399 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 (66550406473) 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, 211943813 + ... + 211944126.

It is an arithmetic number, because the mean of its divisors is an integer number (16743573630).

Almost surely, 2^66550406423 is an apocalyptic number.

66550406423 is a deficient number, since it is larger than the sum of its proper divisors (423888097).

66550406423 is a wasteful number, since it uses less digits than its factorization.

66550406423 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 423888096.

The product of its (nonzero) digits is 518400, while the sum is 41.

The spelling of 66550406423 in words is "sixty-six billion, five hundred fifty million, four hundred six thousand, four hundred twenty-three".