21441923 has 2 divisors, whose sum is σ = 21441924. Its totient is φ = 21441922.

The previous prime is 21441919. The next prime is 21441941. The reversal of 21441923 is 32914412.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21441923 - 2² = 21441919 is a prime.

It is equal to p_1356119 and since 21441923 and 1356119 have the same sum of digits, it is a Honaker prime.

It is a junction number, because it is equal to n+sod(n) for n = 21441892 and 21441901.

It is not a weakly prime, because it can be changed into another prime (21441223) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10720961 + 10720962.

It is an arithmetic number, because the mean of its divisors is an integer number (10720962).

Almost surely, 2^21441923 is an apocalyptic number.

21441923 is a deficient number, since it is larger than the sum of its proper divisors (1).

21441923 is an equidigital number, since it uses as much as digits as its factorization.

21441923 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1728, while the sum is 26.

The square root of 21441923 is about 4630.5424088329. The cubic root of 21441923 is about 277.8142877463.

The spelling of 21441923 in words is "twenty-one million, four hundred forty-one thousand, nine hundred twenty-three".