191641820 has 12 divisors (see below), whose sum is σ = 402447864. Its totient is φ = 76656720.

The previous prime is 191641789. The next prime is 191641823. The reversal of 191641820 is 28146191.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (191641823) 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, 4791026 + ... + 4791065.

It is an arithmetic number, because the mean of its divisors is an integer number (33537322).

Almost surely, 2^191641820 is an apocalyptic number.

191641820 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

191641820 is an abundant number, since it is smaller than the sum of its proper divisors (210806044).

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

191641820 is a wasteful number, since it uses less digits than its factorization.

191641820 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9582100 (or 9582098 counting only the distinct ones).

The product of its (nonzero) digits is 3456, while the sum is 32.

The square root of 191641820 is about 13843.4757196305. The cubic root of 191641820 is about 576.5408652634.

The spelling of 191641820 in words is "one hundred ninety-one million, six hundred forty-one thousand, eight hundred twenty".