168722993 has 2 divisors, whose sum is σ = 168722994. Its totient is φ = 168722992.

The previous prime is 168722881. The next prime is 168722999. The reversal of 168722993 is 399227861.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 147452449 + 21270544 = 12143^2 + 4612^2 .

It is an emirp because it is prime and its reverse (399227861) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 168722993 - 2¹⁴ = 168706609 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (168722999) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 84361496 + 84361497.

It is an arithmetic number, because the mean of its divisors is an integer number (84361497).

Almost surely, 2^168722993 is an apocalyptic number.

It is an amenable number.

168722993 is a deficient number, since it is larger than the sum of its proper divisors (1).

168722993 is an equidigital number, since it uses as much as digits as its factorization.

168722993 is an evil number, because the sum of its binary digits is even.

The product of its digits is 326592, while the sum is 47.

The square root of 168722993 is about 12989.3415152578. The cubic root of 168722993 is about 552.5752433303.

The spelling of 168722993 in words is "one hundred sixty-eight million, seven hundred twenty-two thousand, nine hundred ninety-three".