168353821 has 2 divisors, whose sum is σ = 168353822. Its totient is φ = 168353820.

The previous prime is 168353791. The next prime is 168353833. The reversal of 168353821 is 128353861.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 139570596 + 28783225 = 11814^2 + 5365^2 .

It is a cyclic number.

It is not a de Polignac number, because 168353821 - 2⁵ = 168353789 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (168353891) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 84176910 + 84176911.

It is an arithmetic number, because the mean of its divisors is an integer number (84176911).

Almost surely, 2^168353821 is an apocalyptic number.

It is an amenable number.

168353821 is a deficient number, since it is larger than the sum of its proper divisors (1).

168353821 is an equidigital number, since it uses as much as digits as its factorization.

168353821 is an evil number, because the sum of its binary digits is even.

The product of its digits is 34560, while the sum is 37.

The square root of 168353821 is about 12975.1231593384. The cubic root of 168353821 is about 552.1719308391.

The spelling of 168353821 in words is "one hundred sixty-eight million, three hundred fifty-three thousand, eight hundred twenty-one".