611401312661 has 4 divisors (see below), whose sum is σ = 611413846092. Its totient is φ = 611388779232.

The previous prime is 611401312609. The next prime is 611401312681. The reversal of 611401312661 is 166213104116.

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 137960987761 + 473440324900 = 371431^2 + 688070^2 .

It is a cyclic number.

It is not a de Polignac number, because 611401312661 - 2¹⁸ = 611401050517 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (611401312601) 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, 6193256 + ... + 6291201.

It is an arithmetic number, because the mean of its divisors is an integer number (152853461523).

Almost surely, 2^611401312661 is an apocalyptic number.

It is an amenable number.

611401312661 is a deficient number, since it is larger than the sum of its proper divisors (12533431).

611401312661 is a wasteful number, since it uses less digits than its factorization.

611401312661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12533430.

The product of its (nonzero) digits is 5184, while the sum is 32.

Adding to 611401312661 its reverse (166213104116), we get a palindrome (777614416777).

The spelling of 611401312661 in words is "six hundred eleven billion, four hundred one million, three hundred twelve thousand, six hundred sixty-one".