66748631 has 2 divisors, whose sum is σ = 66748632. Its totient is φ = 66748630.

The previous prime is 66748621. The next prime is 66748639. The reversal of 66748631 is 13684766.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 66748631 - 2⁶ = 66748567 is a prime.

It is a super-2 number, since 2×66748631² = 8910759480748322, which contains 22 as substring.

It is a Sophie Germain prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (66748639) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33374315 + 33374316.

It is an arithmetic number, because the mean of its divisors is an integer number (33374316).

Almost surely, 2^66748631 is an apocalyptic number.

66748631 is a deficient number, since it is larger than the sum of its proper divisors (1).

66748631 is an equidigital number, since it uses as much as digits as its factorization.

66748631 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 145152, while the sum is 41.

The square root of 66748631 is about 8169.9835373151. The cubic root of 66748631 is about 405.6462395267.

The spelling of 66748631 in words is "sixty-six million, seven hundred forty-eight thousand, six hundred thirty-one".