166833521 has 2 divisors, whose sum is σ = 166833522. Its totient is φ = 166833520.

The previous prime is 166833473. The next prime is 166833523. The reversal of 166833521 is 125338661.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 160402225 + 6431296 = 12665^2 + 2536^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-166833521 is a prime.

Together with 166833523, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (166833523) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 83416760 + 83416761.

It is an arithmetic number, because the mean of its divisors is an integer number (83416761).

Almost surely, 2^166833521 is an apocalyptic number.

It is an amenable number.

166833521 is a deficient number, since it is larger than the sum of its proper divisors (1).

166833521 is an equidigital number, since it uses as much as digits as its factorization.

166833521 is an evil number, because the sum of its binary digits is even.

The product of its digits is 25920, while the sum is 35.

The square root of 166833521 is about 12916.4051113303. The cubic root of 166833521 is about 550.5047938552.

The spelling of 166833521 in words is "one hundred sixty-six million, eight hundred thirty-three thousand, five hundred twenty-one".