195801990 has 32 divisors (see below), whose sum is σ = 490358016. Its totient is φ = 49943520.

The previous prime is 195801979. The next prime is 195802003. The reversal of 195801990 is 99108591.

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, 141196 + ... + 142575.

It is an arithmetic number, because the mean of its divisors is an integer number (15323688).

Almost surely, 2^195801990 is an apocalyptic number.

195801990 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

195801990 is an abundant number, since it is smaller than the sum of its proper divisors (294556026).

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

195801990 is a wasteful number, since it uses less digits than its factorization.

195801990 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 283804.

The product of its (nonzero) digits is 29160, while the sum is 42.

The square root of 195801990 is about 13992.9264273060. The cubic root of 195801990 is about 580.6828955993.

The spelling of 195801990 in words is "one hundred ninety-five million, eight hundred one thousand, nine hundred ninety".