19641923 has 4 divisors (see below), whose sum is σ = 22447920. Its totient is φ = 16835928.

The previous prime is 19641917. The next prime is 19641943. The reversal of 19641923 is 32914691.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 32914691 = 1153 ⋅28547.

It is a cyclic number.

It is not a de Polignac number, because 19641923 - 2⁶ = 19641859 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (19641943) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1402988 + ... + 1403001.

It is an arithmetic number, because the mean of its divisors is an integer number (5611980).

Almost surely, 2^19641923 is an apocalyptic number.

19641923 is a deficient number, since it is larger than the sum of its proper divisors (2805997).

19641923 is an equidigital number, since it uses as much as digits as its factorization.

19641923 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2805996.

The product of its digits is 11664, while the sum is 35.

The square root of 19641923 is about 4431.9209153594. The cubic root of 19641923 is about 269.8120456878.

The spelling of 19641923 in words is "nineteen million, six hundred forty-one thousand, nine hundred twenty-three".