1617661779575 has 12 divisors (see below), whose sum is σ = 2075069594040. Its totient is φ = 1249504270560.

The previous prime is 1617661779571. The next prime is 1617661779599. The reversal of 1617661779575 is 5759771667161.

It is not a de Polignac number, because 1617661779575 - 2² = 1617661779571 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1617661779571) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1115628089 + ... + 1115629538.

It is an arithmetic number, because the mean of its divisors is an integer number (172922466170).

Almost surely, 2^{1617661779575} is an apocalyptic number.

1617661779575 is a deficient number, since it is larger than the sum of its proper divisors (457407814465).

1617661779575 is a wasteful number, since it uses less digits than its factorization.

1617661779575 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2231257666 (or 2231257661 counting only the distinct ones).

The product of its digits is 116688600, while the sum is 68.

The spelling of 1617661779575 in words is "one trillion, six hundred seventeen billion, six hundred sixty-one million, seven hundred seventy-nine thousand, five hundred seventy-five".