51663751 has 2 divisors, whose sum is σ = 51663752. Its totient is φ = 51663750.

The previous prime is 51663749. The next prime is 51663791. The reversal of 51663751 is 15736615.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 51663751 - 2¹ = 51663749 is a prime.

Together with 51663749, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (51663791) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25831875 + 25831876.

It is an arithmetic number, because the mean of its divisors is an integer number (25831876).

Almost surely, 2^51663751 is an apocalyptic number.

51663751 is a deficient number, since it is larger than the sum of its proper divisors (1).

51663751 is an equidigital number, since it uses as much as digits as its factorization.

51663751 is an evil number, because the sum of its binary digits is even.

The product of its digits is 18900, while the sum is 34.

The square root of 51663751 is about 7187.7500652151. The cubic root of 51663751 is about 372.4448540799. Note that the first 3 decimals are identical.

The spelling of 51663751 in words is "fifty-one million, six hundred sixty-three thousand, seven hundred fifty-one".