169021997 has 2 divisors, whose sum is σ = 169021998. Its totient is φ = 169021996.

The previous prime is 169021933. The next prime is 169022023. The reversal of 169021997 is 799120961.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 167469481 + 1552516 = 12941^2 + 1246^2 .

It is a cyclic number.

It is not a de Polignac number, because 169021997 - 2⁶ = 169021933 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (169021927) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 84510998 + 84510999.

It is an arithmetic number, because the mean of its divisors is an integer number (84510999).

Almost surely, 2^169021997 is an apocalyptic number.

It is an amenable number.

169021997 is a deficient number, since it is larger than the sum of its proper divisors (1).

169021997 is an equidigital number, since it uses as much as digits as its factorization.

169021997 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 61236, while the sum is 44.

The square root of 169021997 is about 13000.8460109333. The cubic root of 169021997 is about 552.9014677946.

The spelling of 169021997 in words is "one hundred sixty-nine million, twenty-one thousand, nine hundred ninety-seven".