12465656421 has 16 divisors (see below), whose sum is σ = 17083649664. Its totient is φ = 8079407424.

The previous prime is 12465656417. The next prime is 12465656431.

12465656421 is nontrivially palindromic in base 10.

It is not a de Polignac number, because 12465656421 - 2² = 12465656417 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12465656431) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 97776 + ... + 185718.

It is an arithmetic number, because the mean of its divisors is an integer number (1067728104).

Almost surely, 2^12465656421 is an apocalyptic number.

It is an amenable number.

12465656421 is a deficient number, since it is larger than the sum of its proper divisors (4617993243).

12465656421 is a wasteful number, since it uses less digits than its factorization.

12465656421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 89260.

The product of its digits is 345600, while the sum is 42.

The spelling of 12465656421 in words is "twelve billion, four hundred sixty-five million, six hundred fifty-six thousand, four hundred twenty-one".