161603566 has 8 divisors (see below), whose sum is σ = 252944784. Its totient is φ = 77288640.

The previous prime is 161603557. The next prime is 161603567. The reversal of 161603566 is 665306161.

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

It is a super-2 number, since 2×161603566² = 52231425087832712, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (161603567) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1756515 + ... + 1756606.

It is an arithmetic number, because the mean of its divisors is an integer number (31618098).

Almost surely, 2^161603566 is an apocalyptic number.

161603566 is a deficient number, since it is larger than the sum of its proper divisors (91341218).

161603566 is a wasteful number, since it uses less digits than its factorization.

161603566 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3513146.

The product of its (nonzero) digits is 19440, while the sum is 34.

The square root of 161603566 is about 12712.3391238591. The cubic root of 161603566 is about 544.6911427908.

The spelling of 161603566 in words is "one hundred sixty-one million, six hundred three thousand, five hundred sixty-six".