161857047 has 8 divisors (see below), whose sum is σ = 235428480. Its totient is φ = 98095160.

The previous prime is 161856979. The next prime is 161857103. The reversal of 161857047 is 740758161.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 161857047 - 2²⁰ = 160808471 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 161856996 and 161857014.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (161857147) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2452347 + ... + 2452412.

It is an arithmetic number, because the mean of its divisors is an integer number (29428560).

Almost surely, 2^161857047 is an apocalyptic number.

161857047 is a deficient number, since it is larger than the sum of its proper divisors (73571433).

161857047 is a wasteful number, since it uses less digits than its factorization.

161857047 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4904773.

The product of its (nonzero) digits is 47040, while the sum is 39.

The square root of 161857047 is about 12722.3050977407. The cubic root of 161857047 is about 544.9757832294.

It can be divided in two parts, 16185 and 7047, that added together give a palindrome (23232).

The spelling of 161857047 in words is "one hundred sixty-one million, eight hundred fifty-seven thousand, forty-seven".