170809481 has 2 divisors, whose sum is σ = 170809482. Its totient is φ = 170809480.

The previous prime is 170809451. The next prime is 170809537. The reversal of 170809481 is 184908071.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 98406400 + 72403081 = 9920^2 + 8509^2 .

It is a cyclic number.

It is not a de Polignac number, because 170809481 - 2⁶ = 170809417 is a prime.

It is a super-2 number, since 2×170809481² = 58351757598978722, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (170809451) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 85404740 + 85404741.

It is an arithmetic number, because the mean of its divisors is an integer number (85404741).

Almost surely, 2^170809481 is an apocalyptic number.

It is an amenable number.

170809481 is a deficient number, since it is larger than the sum of its proper divisors (1).

170809481 is an equidigital number, since it uses as much as digits as its factorization.

170809481 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 16128, while the sum is 38.

The square root of 170809481 is about 13069.4101244088. The cubic root of 170809481 is about 554.8436981061.

The spelling of 170809481 in words is "one hundred seventy million, eight hundred nine thousand, four hundred eighty-one".