73666391 has 2 divisors, whose sum is σ = 73666392. Its totient is φ = 73666390.

The previous prime is 73666387. The next prime is 73666393. The reversal of 73666391 is 19366637.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 73666391 - 2² = 73666387 is a prime.

Together with 73666393, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (73666393) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 36833195 + 36833196.

It is an arithmetic number, because the mean of its divisors is an integer number (36833196).

Almost surely, 2^73666391 is an apocalyptic number.

73666391 is a deficient number, since it is larger than the sum of its proper divisors (1).

73666391 is an equidigital number, since it uses as much as digits as its factorization.

73666391 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 122472, while the sum is 41.

The square root of 73666391 is about 8582.9127340315. The cubic root of 73666391 is about 419.2017927413.

The spelling of 73666391 in words is "seventy-three million, six hundred sixty-six thousand, three hundred ninety-one".