51086561268866 has 4 divisors (see below), whose sum is σ = 76629841903302. Its totient is φ = 25543280634432.

The previous prime is 51086561268863. The next prime is 51086561268881. The reversal of 51086561268866 is 66886216568015.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 49709761765225 + 1376799503641 = 7050515^2 + 1173371^2 .

It is a junction number, because it is equal to n+sod(n) for n = 51086561268796 and 51086561268805.

It is not an unprimeable number, because it can be changed into a prime (51086561268863) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 12771640317215 + ... + 12771640317218.

Almost surely, 2^{51086561268866} is an apocalyptic number.

51086561268866 is a deficient number, since it is larger than the sum of its proper divisors (25543280634436).

51086561268866 is a wasteful number, since it uses less digits than its factorization.

51086561268866 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 25543280634435.

The product of its (nonzero) digits is 199065600, while the sum is 68.

The spelling of 51086561268866 in words is "fifty-one trillion, eighty-six billion, five hundred sixty-one million, two hundred sixty-eight thousand, eight hundred sixty-six".