523666143921 has 4 divisors (see below), whose sum is σ = 698221525232. Its totient is φ = 349110762612.

The previous prime is 523666143911. The next prime is 523666143937. The reversal of 523666143921 is 129341666325.

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 523666143921 - 2¹⁸ = 523665881777 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 (523666143911) 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, 87277690651 + ... + 87277690656.

It is an arithmetic number, because the mean of its divisors is an integer number (174555381308).

Almost surely, 2^523666143921 is an apocalyptic number.

It is an amenable number.

523666143921 is a deficient number, since it is larger than the sum of its proper divisors (174555381311).

523666143921 is a wasteful number, since it uses less digits than its factorization.

523666143921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 174555381310.

The product of its digits is 1399680, while the sum is 48.

The spelling of 523666143921 in words is "five hundred twenty-three billion, six hundred sixty-six million, one hundred forty-three thousand, nine hundred twenty-one".