31728267823 has 4 divisors (see below), whose sum is σ = 36260877520. Its totient is φ = 27195658128.

The previous prime is 31728267817. The next prime is 31728267871. The reversal of 31728267823 is 32876282713.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 32876282713 = 53 ⋅620307221.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-31728267823 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31728267023) 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, 2266304838 + ... + 2266304851.

It is an arithmetic number, because the mean of its divisors is an integer number (9065219380).

Almost surely, 2^31728267823 is an apocalyptic number.

31728267823 is a deficient number, since it is larger than the sum of its proper divisors (4532609697).

31728267823 is an equidigital number, since it uses as much as digits as its factorization.

31728267823 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4532609696.

The product of its digits is 1354752, while the sum is 49.

The spelling of 31728267823 in words is "thirty-one billion, seven hundred twenty-eight million, two hundred sixty-seven thousand, eight hundred twenty-three".