19491930 has 24 divisors (see below), whose sum is σ = 50679252. Its totient is φ = 5197824.

The previous prime is 19491919. The next prime is 19491931. The reversal of 19491930 is 3919491.

It can be written as a sum of positive squares in 2 ways, for example, as 18740241 + 751689 = 4329^2 + 867^2 .

It is not an unprimeable number, because it can be changed into a prime (19491931) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 108199 + ... + 108378.

Almost surely, 2^19491930 is an apocalyptic number.

19491930 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

19491930 is an abundant number, since it is smaller than the sum of its proper divisors (31187322).

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

19491930 is a wasteful number, since it uses less digits than its factorization.

19491930 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 216590 (or 216587 counting only the distinct ones).

The product of its (nonzero) digits is 8748, while the sum is 36.

The square root of 19491930 is about 4414.9665910401. The cubic root of 19491930 is about 269.1234951172.

The spelling of 19491930 in words is "nineteen million, four hundred ninety-one thousand, nine hundred thirty".