12721328634 has 32 divisors (see below), whose sum is σ = 29306290176. Its totient is φ = 3606044400.

The previous prime is 12721328623. The next prime is 12721328651. The reversal of 12721328634 is 43682312721.

It is a junction number, because it is equal to n+sod(n) for n = 12721328592 and 12721328601.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1187142 + ... + 1197809.

It is an arithmetic number, because the mean of its divisors is an integer number (915821568).

Almost surely, 2^12721328634 is an apocalyptic number.

12721328634 is a gapful number since it is divisible by the number (14) formed by its first and last digit.

12721328634 is an abundant number, since it is smaller than the sum of its proper divisors (16584961542).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

12721328634 is a wasteful number, since it uses less digits than its factorization.

12721328634 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2385090.

The product of its digits is 96768, while the sum is 39.

The spelling of 12721328634 in words is "twelve billion, seven hundred twenty-one million, three hundred twenty-eight thousand, six hundred thirty-four".