666554120125 has 8 divisors (see below), whose sum is σ = 831859542072. Its totient is φ = 533243296000.

The previous prime is 666554120123. The next prime is 666554120159. The reversal of 666554120125 is 521021455666.

It can be written as a sum of positive squares in 4 ways, for example, as 81774265444 + 584779854681 = 285962^2 + 764709^2 .

It is not a de Polignac number, because 666554120125 - 2¹ = 666554120123 is a prime.

It is a super-2 number, since 2×666554120125² (a number of 24 digits) contains 22 as substring.

It is a hoax number, since the sum of its digits (43) coincides with the sum of the digits of its distinct prime factors.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (666554120123) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2666216356 + ... + 2666216605.

It is an arithmetic number, because the mean of its divisors is an integer number (103982442759).

Almost surely, 2^666554120125 is an apocalyptic number.

It is an amenable number.

666554120125 is a deficient number, since it is larger than the sum of its proper divisors (165305421947).

666554120125 is an equidigital number, since it uses as much as digits as its factorization.

666554120125 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5332432976 (or 5332432966 counting only the distinct ones).

The product of its (nonzero) digits is 432000, while the sum is 43.

The spelling of 666554120125 in words is "six hundred sixty-six billion, five hundred fifty-four million, one hundred twenty thousand, one hundred twenty-five".