161209471 has 4 divisors (see below), whose sum is σ = 169694200. Its totient is φ = 152724744.

The previous prime is 161209439. The next prime is 161209501. The reversal of 161209471 is 174902161.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 161209471 - 2⁵ = 161209439 is a prime.

It is a super-3 number, since 3×161209471³ (a number of 26 digits) contains 333 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (161209421) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4242336 + ... + 4242373.

It is an arithmetic number, because the mean of its divisors is an integer number (42423550).

Almost surely, 2^161209471 is an apocalyptic number.

161209471 is a deficient number, since it is larger than the sum of its proper divisors (8484729).

161209471 is an equidigital number, since it uses as much as digits as its factorization.

161209471 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8484728.

The product of its (nonzero) digits is 3024, while the sum is 31.

The square root of 161209471 is about 12696.8291710962. The cubic root of 161209471 is about 544.2480115080.

The spelling of 161209471 in words is "one hundred sixty-one million, two hundred nine thousand, four hundred seventy-one".