51666903 has 24 divisors (see below), whose sum is σ = 78296400. Its totient is φ = 34043328.

The previous prime is 51666899. The next prime is 51666941. The reversal of 51666903 is 30966615.

It is not a de Polignac number, because 51666903 - 2² = 51666899 is a prime.

It is a super-2 number, since 2×51666903² = 5338937731222818, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51666103) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 20433 + ... + 22821.

It is an arithmetic number, because the mean of its divisors is an integer number (3262350).

Almost surely, 2^51666903 is an apocalyptic number.

51666903 is a deficient number, since it is larger than the sum of its proper divisors (26629497).

51666903 is an equidigital number, since it uses as much as digits as its factorization.

51666903 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2493 (or 2481 counting only the distinct ones).

The product of its (nonzero) digits is 29160, while the sum is 36.

The square root of 51666903 is about 7187.9693238077. The cubic root of 51666903 is about 372.4524281996.

The spelling of 51666903 in words is "fifty-one million, six hundred sixty-six thousand, nine hundred three".