161643000 has 64 divisors (see below), whose sum is σ = 504335520. Its totient is φ = 43104000.

The previous prime is 161642983. The next prime is 161643017. The reversal of 161643000 is 346161.

It is an interprime number because it is at equal distance from previous prime (161642983) and next prime (161643017).

It is a super-2 number, since 2×161643000² = 52256918898000000, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 23941 + ... + 29940.

Almost surely, 2^161643000 is an apocalyptic number.

161643000 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

161643000 is an abundant number, since it is smaller than the sum of its proper divisors (342692520).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

161643000 is a wasteful number, since it uses less digits than its factorization.

161643000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 53905 (or 53891 counting only the distinct ones).

The product of its (nonzero) digits is 432, while the sum is 21.

The square root of 161643000 is about 12713.8900419974. The cubic root of 161643000 is about 544.7354438009.

Adding to 161643000 its reverse (346161), we get a palindrome (161989161).

The spelling of 161643000 in words is "one hundred sixty-one million, six hundred forty-three thousand".