66433661431 has 4 divisors (see below), whose sum is σ = 68229165832. Its totient is φ = 64638157032.

The previous prime is 66433661423. The next prime is 66433661471. The reversal of 66433661431 is 13416633466.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 13416633466 = 2 ⋅6708316733.

It is a cyclic number.

It is not a de Polignac number, because 66433661431 - 2³ = 66433661423 is a prime.

It is a super-2 number, since 2×66433661431² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66433661401) 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, 897752145 + ... + 897752218.

It is an arithmetic number, because the mean of its divisors is an integer number (17057291458).

Almost surely, 2^66433661431 is an apocalyptic number.

66433661431 is a deficient number, since it is larger than the sum of its proper divisors (1795504401).

66433661431 is a wasteful number, since it uses less digits than its factorization.

66433661431 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1795504400.

The product of its digits is 559872, while the sum is 43.

The spelling of 66433661431 in words is "sixty-six billion, four hundred thirty-three million, six hundred sixty-one thousand, four hundred thirty-one".