1666505287504 has 20 divisors (see below), whose sum is σ = 3229806844980. Its totient is φ = 833006746880.

The previous prime is 1666505287487. The next prime is 1666505287543. The reversal of 1666505287504 is 4057825056661.

It can be written as a sum of positive squares in 2 ways, for example, as 926698873104 + 739806414400 = 962652^2 + 860120^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 15312637 + ... + 15421084.

It is an arithmetic number, because the mean of its divisors is an integer number (161490342249).

Almost surely, 2^{1666505287504} is an apocalyptic number.

It is an amenable number.

1666505287504 is a deficient number, since it is larger than the sum of its proper divisors (1563301557476).

1666505287504 is a wasteful number, since it uses less digits than its factorization.

1666505287504 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 30737118 (or 30737112 counting only the distinct ones).

The product of its (nonzero) digits is 12096000, while the sum is 55.

The spelling of 1666505287504 in words is "one trillion, six hundred sixty-six billion, five hundred five million, two hundred eighty-seven thousand, five hundred four".