20165471 has 2 divisors, whose sum is σ = 20165472. Its totient is φ = 20165470.

The previous prime is 20165449. The next prime is 20165473. The reversal of 20165471 is 17456102.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 20165471 - 2²² = 15971167 is a prime.

It is a super-3 number, since 3×20165471³ (a number of 23 digits) contains 333 as substring.

Together with 20165473, it forms a pair of twin primes.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 20165471.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20165473) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10082735 + 10082736.

It is an arithmetic number, because the mean of its divisors is an integer number (10082736).

Almost surely, 2^20165471 is an apocalyptic number.

20165471 is a deficient number, since it is larger than the sum of its proper divisors (1).

20165471 is an equidigital number, since it uses as much as digits as its factorization.

20165471 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1680, while the sum is 26.

The square root of 20165471 is about 4490.5980670730. The cubic root of 20165471 is about 272.1883022447.

The spelling of 20165471 in words is "twenty million, one hundred sixty-five thousand, four hundred seventy-one".