12351721521 has 8 divisors (see below), whose sum is σ = 16482432960. Its totient is φ = 8227745552.

The previous prime is 12351721519. The next prime is 12351721537. The reversal of 12351721521 is 12512715321.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 12351721521 - 2¹ = 12351721519 is a prime.

It is not an unprimeable number, because it can be changed into a prime (12351721511) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1679586 + ... + 1686923.

It is an arithmetic number, because the mean of its divisors is an integer number (2060304120).

Almost surely, 2^12351721521 is an apocalyptic number.

It is an amenable number.

12351721521 is a deficient number, since it is larger than the sum of its proper divisors (4130711439).

12351721521 is a wasteful number, since it uses less digits than its factorization.

12351721521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3367735.

The product of its digits is 4200, while the sum is 30.

The spelling of 12351721521 in words is "twelve billion, three hundred fifty-one million, seven hundred twenty-one thousand, five hundred twenty-one".