12547101921 has 4 divisors (see below), whose sum is σ = 16729469232. Its totient is φ = 8364734612.

The previous prime is 12547101823. The next prime is 12547101929. The reversal of 12547101921 is 12910174521.

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 a cyclic number.

It is not a de Polignac number, because 12547101921 - 2¹⁹ = 12546577633 is a prime.

It is not an unprimeable number, because it can be changed into a prime (12547101929) 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, 2091183651 + ... + 2091183656.

It is an arithmetic number, because the mean of its divisors is an integer number (4182367308).

Almost surely, 2^12547101921 is an apocalyptic number.

It is an amenable number.

12547101921 is a deficient number, since it is larger than the sum of its proper divisors (4182367311).

12547101921 is an equidigital number, since it uses as much as digits as its factorization.

12547101921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4182367310.

The product of its (nonzero) digits is 5040, while the sum is 33.

The spelling of 12547101921 in words is "twelve billion, five hundred forty-seven million, one hundred one thousand, nine hundred twenty-one".