661020244411 has 4 divisors (see below), whose sum is σ = 661021870824. Its totient is φ = 661018618000.

The previous prime is 661020244397. The next prime is 661020244471. The reversal of 661020244411 is 114442020166.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 114442020166 = 2 ⋅57221010083.

It is a cyclic number.

It is not a de Polignac number, because 661020244411 - 2³³ = 652430309819 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (661020244471) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 381336 + ... + 1211386.

It is an arithmetic number, because the mean of its divisors is an integer number (165255467706).

Almost surely, 2^661020244411 is an apocalyptic number.

661020244411 is a deficient number, since it is larger than the sum of its proper divisors (1626413).

661020244411 is an equidigital number, since it uses as much as digits as its factorization.

661020244411 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1626412.

The product of its (nonzero) digits is 9216, while the sum is 31.

Adding to 661020244411 its reverse (114442020166), we get a palindrome (775462264577).

The spelling of 661020244411 in words is "six hundred sixty-one billion, twenty million, two hundred forty-four thousand, four hundred eleven".