655065510661 has 4 divisors (see below), whose sum is σ = 693598776012. Its totient is φ = 616532245312.

The previous prime is 655065510623. The next prime is 655065510689. The reversal of 655065510661 is 166015560556.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 444480889636 + 210584621025 = 666694^2 + 458895^2 .

It is a cyclic number.

It is not a de Polignac number, because 655065510661 - 2¹⁵ = 655065477893 is a prime.

It is a super-2 number, since 2×655065510661² (a number of 24 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (655065510061) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 19266632650 + ... + 19266632683.

It is an arithmetic number, because the mean of its divisors is an integer number (173399694003).

Almost surely, 2^655065510661 is an apocalyptic number.

It is an amenable number.

655065510661 is a deficient number, since it is larger than the sum of its proper divisors (38533265351).

655065510661 is a wasteful number, since it uses less digits than its factorization.

655065510661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 38533265350.

The product of its (nonzero) digits is 810000, while the sum is 46.

The spelling of 655065510661 in words is "six hundred fifty-five billion, sixty-five million, five hundred ten thousand, six hundred sixty-one".