12525457821 has 16 divisors (see below), whose sum is σ = 16935317760. Its totient is φ = 8233243200.

The previous prime is 12525457817. The next prime is 12525457853. The reversal of 12525457821 is 12875452521.

It is not a de Polignac number, because 12525457821 - 2² = 12525457817 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12525457891) 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, 137671 + ... + 209771.

It is an arithmetic number, because the mean of its divisors is an integer number (1058457360).

Almost surely, 2^12525457821 is an apocalyptic number.

It is an amenable number.

12525457821 is a deficient number, since it is larger than the sum of its proper divisors (4409859939).

12525457821 is an equidigital number, since it uses as much as digits as its factorization.

12525457821 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 72916.

The product of its digits is 224000, while the sum is 42.

The spelling of 12525457821 in words is "twelve billion, five hundred twenty-five million, four hundred fifty-seven thousand, eight hundred twenty-one".