506776643721 has 8 divisors (see below), whose sum is σ = 750780212960. Its totient is φ = 337851095796.

The previous prime is 506776643699. The next prime is 506776643729. The reversal of 506776643721 is 127346677605.

It is a happy number.

506776643721 is a `hidden beast` number, since 506 + 7 + 7 + 6 + 64 + 3 + 72 + 1 = 666.

It is not a de Polignac number, because 506776643721 - 2¹⁴ = 506776627337 is a prime.

It is a super-2 number, since 2×506776643721² (a number of 24 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (506776643729) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 9384752635 + ... + 9384752688.

It is an arithmetic number, because the mean of its divisors is an integer number (93847526620).

Almost surely, 2^506776643721 is an apocalyptic number.

It is an amenable number.

506776643721 is a deficient number, since it is larger than the sum of its proper divisors (244003569239).

506776643721 is a wasteful number, since it uses less digits than its factorization.

506776643721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18769505332 (or 18769505326 counting only the distinct ones).

The product of its (nonzero) digits is 8890560, while the sum is 54.

The spelling of 506776643721 in words is "five hundred six billion, seven hundred seventy-six million, six hundred forty-three thousand, seven hundred twenty-one".