511287908661 has 12 divisors (see below), whose sum is σ = 781969742892. Its totient is φ = 320808099456.

The previous prime is 511287908657. The next prime is 511287908671. The reversal of 511287908661 is 166809782115.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 275237686161 + 236050222500 = 524631^2 + 485850^2 .

It is not a de Polignac number, because 511287908661 - 2² = 511287908657 is a prime.

It is a super-2 number, since 2×511287908661² (a number of 24 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 511287908598 and 511287908607.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (511287908641) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1670875366 + ... + 1670875671.

It is an arithmetic number, because the mean of its divisors is an integer number (65164145241).

Almost surely, 2^511287908661 is an apocalyptic number.

511287908661 is a gapful number since it is divisible by the number (51) formed by its first and last digit.

It is an amenable number.

511287908661 is a deficient number, since it is larger than the sum of its proper divisors (270681834231).

511287908661 is a wasteful number, since it uses less digits than its factorization.

511287908661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3341751060 (or 3341751057 counting only the distinct ones).

The product of its (nonzero) digits is 1451520, while the sum is 54.

The spelling of 511287908661 in words is "five hundred eleven billion, two hundred eighty-seven million, nine hundred eight thousand, six hundred sixty-one".