4121999666825 has 6 divisors (see below), whose sum is σ = 5111279586894. Its totient is φ = 3297599733440.

The previous prime is 4121999666821. The next prime is 4121999666839. The reversal of 4121999666825 is 5286669991214.

It can be written as a sum of positive squares in 3 ways, for example, as 17117012224 + 4104882654601 = 130832^2 + 2026051^2 .

It is not a de Polignac number, because 4121999666825 - 2² = 4121999666821 is a prime.

It is a super-2 number, since 2×4121999666825² (a number of 26 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (4121999666821) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 82439993312 + ... + 82439993361.

It is an arithmetic number, because the mean of its divisors is an integer number (851879931149).

Almost surely, 2^{4121999666825} is an apocalyptic number.

It is an amenable number.

4121999666825 is a deficient number, since it is larger than the sum of its proper divisors (989279920069).

4121999666825 is a wasteful number, since it uses less digits than its factorization.

4121999666825 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 164879986683 (or 164879986678 counting only the distinct ones).

The product of its digits is 100776960, while the sum is 68.

The spelling of 4121999666825 in words is "four trillion, one hundred twenty-one billion, nine hundred ninety-nine million, six hundred sixty-six thousand, eight hundred twenty-five".