51100666 has 4 divisors (see below), whose sum is σ = 76651002. Its totient is φ = 25550332.

The previous prime is 51100661. The next prime is 51100729. The reversal of 51100666 is 66600115.

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., 43837641 + 7263025 = 6621^2 + 2695^2 .

It is a super-4 number, since 4×51100666⁴ (a number of 32 digits) contains 4444 as substring. Note that it is a super-d number also for d = 2.

It is a self number, because there is not a number n which added to its sum of digits gives 51100666.

It is not an unprimeable number, because it can be changed into a prime (51100661) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 12775165 + ... + 12775168.

Almost surely, 2^51100666 is an apocalyptic number.

51100666 is a deficient number, since it is larger than the sum of its proper divisors (25550336).

51100666 is a wasteful number, since it uses less digits than its factorization.

51100666 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25550335.

The product of its (nonzero) digits is 1080, while the sum is 25.

The square root of 51100666 is about 7148.4729837917. The cubic root of 51100666 is about 371.0868118546.

The spelling of 51100666 in words is "fifty-one million, one hundred thousand, six hundred sixty-six".