19211930 has 16 divisors (see below), whose sum is σ = 34641864. Its totient is φ = 7671360.

The previous prime is 19211897. The next prime is 19211939. The reversal of 19211930 is 3911291.

It can be written as a sum of positive squares in 4 ways, for example, as 19193161 + 18769 = 4381^2 + 137^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 19211930.

It is not an unprimeable number, because it can be changed into a prime (19211939) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 6020 + ... + 8640.

Almost surely, 2^19211930 is an apocalyptic number.

19211930 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

19211930 is a deficient number, since it is larger than the sum of its proper divisors (15429934).

19211930 is a wasteful number, since it uses less digits than its factorization.

19211930 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3361.

The product of its (nonzero) digits is 486, while the sum is 26.

The square root of 19211930 is about 4383.1415674149. The cubic root of 19211930 is about 267.8286292103.

The spelling of 19211930 in words is "nineteen million, two hundred eleven thousand, nine hundred thirty".