51678857 has 2 divisors, whose sum is σ = 51678858. Its totient is φ = 51678856.

The previous prime is 51678853. The next prime is 51678883. The reversal of 51678857 is 75887615.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 33051001 + 18627856 = 5749^2 + 4316^2 .

It is a cyclic number.

It is not a de Polignac number, because 51678857 - 2² = 51678853 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (51678853) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25839428 + 25839429.

It is an arithmetic number, because the mean of its divisors is an integer number (25839429).

Almost surely, 2^51678857 is an apocalyptic number.

It is an amenable number.

51678857 is a deficient number, since it is larger than the sum of its proper divisors (1).

51678857 is an equidigital number, since it uses as much as digits as its factorization.

51678857 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 470400, while the sum is 47.

The square root of 51678857 is about 7188.8008040284. The cubic root of 51678857 is about 372.4811503457.

The spelling of 51678857 in words is "fifty-one million, six hundred seventy-eight thousand, eight hundred fifty-seven".