511223146661 has 4 divisors (see below), whose sum is σ = 511240816800. Its totient is φ = 511205476524.

The previous prime is 511223146633. The next prime is 511223146757. The reversal of 511223146661 is 166641322115.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 511223146661 - 2⁶ = 511223146597 is a prime.

It is a super-2 number, since 2×511223146661² (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 (511223146631) 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, 8791601 + ... + 8849558.

It is an arithmetic number, because the mean of its divisors is an integer number (127810204200).

Almost surely, 2^511223146661 is an apocalyptic number.

It is an amenable number.

511223146661 is a deficient number, since it is larger than the sum of its proper divisors (17670139).

511223146661 is a wasteful number, since it uses less digits than its factorization.

511223146661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17670138.

The product of its digits is 51840, while the sum is 38.

Adding to 511223146661 its reverse (166641322115), we get a palindrome (677864468776).

The spelling of 511223146661 in words is "five hundred eleven billion, two hundred twenty-three million, one hundred forty-six thousand, six hundred sixty-one".