66955631 has 2 divisors, whose sum is σ = 66955632. Its totient is φ = 66955630.

The previous prime is 66955591. The next prime is 66955643. The reversal of 66955631 is 13655966.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 66955631 - 2¹⁰ = 66954607 is a prime.

It is a super-2 number, since 2×66955631² = 8966113045216322, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (66955661) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33477815 + 33477816.

It is an arithmetic number, because the mean of its divisors is an integer number (33477816).

Almost surely, 2^66955631 is an apocalyptic number.

66955631 is a deficient number, since it is larger than the sum of its proper divisors (1).

66955631 is an equidigital number, since it uses as much as digits as its factorization.

66955631 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 145800, while the sum is 41.

The square root of 66955631 is about 8182.6420549844. The cubic root of 66955631 is about 406.0651351085.

The spelling of 66955631 in words is "sixty-six million, nine hundred fifty-five thousand, six hundred thirty-one".