12551145021 has 16 divisors (see below), whose sum is σ = 18945126720. Its totient is φ = 8209553040.

The previous prime is 12551145007. The next prime is 12551145023. The reversal of 12551145021 is 12054115521.

It is a happy number.

12551145021 is a `hidden beast` number, since 125 + 511 + 4 + 5 + 0 + 21 = 666.

It is a de Polignac number, because none of the positive numbers 2^k-12551145021 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12551145023) 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, 4384015 + ... + 4386876.

It is an arithmetic number, because the mean of its divisors is an integer number (1184070420).

Almost surely, 2^12551145021 is an apocalyptic number.

It is an amenable number.

12551145021 is a deficient number, since it is larger than the sum of its proper divisors (6393981699).

12551145021 is an equidigital number, since it uses as much as digits as its factorization.

12551145021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8770953 (or 8770947 counting only the distinct ones).

The product of its (nonzero) digits is 2000, while the sum is 27.

The spelling of 12551145021 in words is "twelve billion, five hundred fifty-one million, one hundred forty-five thousand, twenty-one".