12521643649 has 8 divisors (see below), whose sum is σ = 12641106240. Its totient is φ = 12402226416.

The previous prime is 12521643643. The next prime is 12521643653. The reversal of 12521643649 is 94634612521.

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 12521643649 - 2⁷ = 12521643521 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (12521643643) 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, 856132 + ... + 870634.

It is an arithmetic number, because the mean of its divisors is an integer number (1580138280).

Almost surely, 2^12521643649 is an apocalyptic number.

It is an amenable number.

12521643649 is a deficient number, since it is larger than the sum of its proper divisors (119462591).

12521643649 is a wasteful number, since it uses less digits than its factorization.

12521643649 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22679.

The product of its digits is 311040, while the sum is 43.

The spelling of 12521643649 in words is "twelve billion, five hundred twenty-one million, six hundred forty-three thousand, six hundred forty-nine".