161656541 has 8 divisors (see below), whose sum is σ = 170676480. Its totient is φ = 152687808.

The previous prime is 161656531. The next prime is 161656549. The reversal of 161656541 is 145656161.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-161656541 is a prime.

It is a super-2 number, since 2×161656541² = 52265674496169362, which contains 22 as substring.

It is an alternating number because its digits alternate between odd and even.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (161656549) 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, 6221 + ... + 19026.

It is an arithmetic number, because the mean of its divisors is an integer number (21334560).

Almost surely, 2^161656541 is an apocalyptic number.

It is an amenable number.

161656541 is a deficient number, since it is larger than the sum of its proper divisors (9019939).

161656541 is a wasteful number, since it uses less digits than its factorization.

161656541 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 25603.

The product of its digits is 21600, while the sum is 35.

The square root of 161656541 is about 12714.4225586536. The cubic root of 161656541 is about 544.7506543919.

The spelling of 161656541 in words is "one hundred sixty-one million, six hundred fifty-six thousand, five hundred forty-one".