10091820 has 24 divisors (see below), whose sum is σ = 28257264. Its totient is φ = 2691136.

The previous prime is 10091813. The next prime is 10091821. The reversal of 10091820 is 2819001.

Added to its reverse (2819001) it gives a triangular number (12910821 = T₅₀₈₁).

It is not an unprimeable number, because it can be changed into a prime (10091821) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 84039 + ... + 84158.

It is an arithmetic number, because the mean of its divisors is an integer number (1177386).

Almost surely, 2^10091820 is an apocalyptic number.

10091820 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

10091820 is an abundant number, since it is smaller than the sum of its proper divisors (18165444).

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

10091820 is a wasteful number, since it uses less digits than its factorization.

10091820 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 168209 (or 168207 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 21.

The square root of 10091820 is about 3176.7625029265. The cubic root of 10091820 is about 216.1008616742.

Adding to 10091820 its reverse (2819001), we get a triangular number (12910821 = T₅₀₈₁).

The spelling of 10091820 in words is "ten million, ninety-one thousand, eight hundred twenty".