161857045 has 48 divisors (see below), whose sum is σ = 236653056. Its totient is φ = 105840000.

The previous prime is 161856979. The next prime is 161857103. The reversal of 161857045 is 540758161.

It is not a de Polignac number, because 161857045 - 2⁹ = 161856533 is a prime.

It is a super-2 number, since 2×161857045² = 52395406032264050, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 161856995 and 161857013.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 766990 + ... + 767200.

It is an arithmetic number, because the mean of its divisors is an integer number (4930272).

Almost surely, 2^161857045 is an apocalyptic number.

It is an amenable number.

161857045 is a deficient number, since it is larger than the sum of its proper divisors (74796011).

161857045 is a wasteful number, since it uses less digits than its factorization.

161857045 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 362 (or 355 counting only the distinct ones).

The product of its (nonzero) digits is 33600, while the sum is 37.

The square root of 161857045 is about 12722.3050191386. The cubic root of 161857045 is about 544.9757809848.

The spelling of 161857045 in words is "one hundred sixty-one million, eight hundred fifty-seven thousand, forty-five".