161800870 has 32 divisors (see below), whose sum is σ = 363108096. Its totient is φ = 50431200.

The previous prime is 161800861. The next prime is 161800871. The reversal of 161800870 is 78008161.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (161800871) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 104296 + ... + 105835.

It is an arithmetic number, because the mean of its divisors is an integer number (11347128).

Almost surely, 2^161800870 is an apocalyptic number.

161800870 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

161800870 is an abundant number, since it is smaller than the sum of its proper divisors (201307226).

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

161800870 is a wasteful number, since it uses less digits than its factorization.

161800870 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 210156.

The product of its (nonzero) digits is 2688, while the sum is 31.

The square root of 161800870 is about 12720.0970908244. The cubic root of 161800870 is about 544.9127262546.

The spelling of 161800870 in words is "one hundred sixty-one million, eight hundred thousand, eight hundred seventy".