166520441 has 2 divisors, whose sum is σ = 166520442. Its totient is φ = 166520440.

The previous prime is 166520429. The next prime is 166520443. The reversal of 166520441 is 144025661.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 166513216 + 7225 = 12904^2 + 85^2 .

It is a cyclic number.

It is not a de Polignac number, because 166520441 - 2⁶ = 166520377 is a prime.

Together with 166520443, 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 (166520443) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 83260220 + 83260221.

It is an arithmetic number, because the mean of its divisors is an integer number (83260221).

Almost surely, 2^166520441 is an apocalyptic number.

It is an amenable number.

166520441 is a deficient number, since it is larger than the sum of its proper divisors (1).

166520441 is an equidigital number, since it uses as much as digits as its factorization.

166520441 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 5760, while the sum is 29.

The square root of 166520441 is about 12904.2799489162. The cubic root of 166520441 is about 550.1602188873.

The spelling of 166520441 in words is "one hundred sixty-six million, five hundred twenty thousand, four hundred forty-one".