66662443541 has 4 divisors (see below), whose sum is σ = 66664608192. Its totient is φ = 66660278892.

The previous prime is 66662443517. The next prime is 66662443567. The reversal of 66662443541 is 14534426666.

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, and also an emirpimes, since its reverse is a distinct semiprime: 14534426666 = 2 ⋅7267213333.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-66662443541 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 (66662443501) 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, 1035455 + ... + 1097948.

It is an arithmetic number, because the mean of its divisors is an integer number (16666152048).

Almost surely, 2^66662443541 is an apocalyptic number.

It is an amenable number.

66662443541 is a deficient number, since it is larger than the sum of its proper divisors (2164651).

66662443541 is a wasteful number, since it uses less digits than its factorization.

66662443541 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2164650.

The product of its digits is 2488320, while the sum is 47.

The spelling of 66662443541 in words is "sixty-six billion, six hundred sixty-two million, four hundred forty-three thousand, five hundred forty-one".