12649520491 has 4 divisors (see below), whose sum is σ = 12650687800. Its totient is φ = 12648353184.

The previous prime is 12649520489. The next prime is 12649520551. The reversal of 12649520491 is 19402594621.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 12649520491 - 2¹ = 12649520489 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (12649520591) 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, 567246 + ... + 589123.

It is an arithmetic number, because the mean of its divisors is an integer number (3162671950).

Almost surely, 2^12649520491 is an apocalyptic number.

12649520491 is a deficient number, since it is larger than the sum of its proper divisors (1167309).

12649520491 is a wasteful number, since it uses less digits than its factorization.

12649520491 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1167308.

The product of its (nonzero) digits is 155520, while the sum is 43.

The spelling of 12649520491 in words is "twelve billion, six hundred forty-nine million, five hundred twenty thousand, four hundred ninety-one".