66951623 has 2 divisors, whose sum is σ = 66951624. Its totient is φ = 66951622.

The previous prime is 66951617. The next prime is 66951637. The reversal of 66951623 is 32615966.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 66951623 - 2¹² = 66947527 is a prime.

It is equal to p_3949085 and since 66951623 and 3949085 have the same sum of digits, it is a Honaker prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (66951613) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33475811 + 33475812.

It is an arithmetic number, because the mean of its divisors is an integer number (33475812).

Almost surely, 2^66951623 is an apocalyptic number.

66951623 is a deficient number, since it is larger than the sum of its proper divisors (1).

66951623 is an equidigital number, since it uses as much as digits as its factorization.

66951623 is an evil number, because the sum of its binary digits is even.

The product of its digits is 58320, while the sum is 38.

The square root of 66951623 is about 8182.3971426471. The cubic root of 66951623 is about 406.0570325212.

The spelling of 66951623 in words is "sixty-six million, nine hundred fifty-one thousand, six hundred twenty-three".