168939649 has 2 divisors, whose sum is σ = 168939650. Its totient is φ = 168939648.

The previous prime is 168939643. The next prime is 168939709. The reversal of 168939649 is 946939861.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 167236624 + 1703025 = 12932^2 + 1305^2 .

It is a cyclic number.

It is not a de Polignac number, because 168939649 - 2⁹ = 168939137 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 168939649.

It is not a weakly prime, because it can be changed into another prime (168939643) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 84469824 + 84469825.

It is an arithmetic number, because the mean of its divisors is an integer number (84469825).

Almost surely, 2^168939649 is an apocalyptic number.

It is an amenable number.

168939649 is a deficient number, since it is larger than the sum of its proper divisors (1).

168939649 is an equidigital number, since it uses as much as digits as its factorization.

168939649 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2519424, while the sum is 55.

The square root of 168939649 is about 12997.6786004271. The cubic root of 168939649 is about 552.8116614833.

The spelling of 168939649 in words is "one hundred sixty-eight million, nine hundred thirty-nine thousand, six hundred forty-nine".