1866408815225 has 24 divisors (see below), whose sum is σ = 2447271697920. Its totient is φ = 1409718672000.

The previous prime is 1866408815221. The next prime is 1866408815231. The reversal of 1866408815225 is 5225188046681.

It is not a de Polignac number, because 1866408815225 - 2² = 1866408815221 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1866408815221) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 29337365 + ... + 29400914.

It is an arithmetic number, because the mean of its divisors is an integer number (101969654080).

Almost surely, 2^{1866408815225} is an apocalyptic number.

It is an amenable number.

1866408815225 is a deficient number, since it is larger than the sum of its proper divisors (580862882695).

1866408815225 is a wasteful number, since it uses less digits than its factorization.

1866408815225 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 58738361 (or 58738356 counting only the distinct ones).

The product of its (nonzero) digits is 7372800, while the sum is 56.

The spelling of 1866408815225 in words is "one trillion, eight hundred sixty-six billion, four hundred eight million, eight hundred fifteen thousand, two hundred twenty-five".