1663440315655 has 16 divisors (see below), whose sum is σ = 2090659792320. Its totient is φ = 1268161489408.

The previous prime is 1663440315619. The next prime is 1663440315671. The reversal of 1663440315655 is 5565130443661.

It is a cyclic number.

It is not a de Polignac number, because 1663440315655 - 2¹¹ = 1663440313607 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1663440315599 and 1663440315608.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 26855122 + ... + 26916991.

It is an arithmetic number, because the mean of its divisors is an integer number (130666237020).

Almost surely, 2^{1663440315655} is an apocalyptic number.

1663440315655 is a deficient number, since it is larger than the sum of its proper divisors (427219476665).

1663440315655 is a wasteful number, since it uses less digits than its factorization.

1663440315655 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 53772410.

The product of its (nonzero) digits is 3888000, while the sum is 49.

The spelling of 1663440315655 in words is "one trillion, six hundred sixty-three billion, four hundred forty million, three hundred fifteen thousand, six hundred fifty-five".