667681093 has 2 divisors, whose sum is σ = 667681094. Its totient is φ = 667681092.

The previous prime is 667681087. The next prime is 667681097. The reversal of 667681093 is 390186766.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 631114884 + 36566209 = 25122^2 + 6047^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-667681093 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (667681097) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 333840546 + 333840547.

It is an arithmetic number, because the mean of its divisors is an integer number (333840547).

Almost surely, 2^667681093 is an apocalyptic number.

It is an amenable number.

667681093 is a deficient number, since it is larger than the sum of its proper divisors (1).

667681093 is an equidigital number, since it uses as much as digits as its factorization.

667681093 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 326592, while the sum is 46.

The square root of 667681093 is about 25839.5257889923. The cubic root of 667681093 is about 874.0233316981.

The spelling of 667681093 in words is "six hundred sixty-seven million, six hundred eighty-one thousand, ninety-three".