21035423 has 4 divisors (see below), whose sum is σ = 21380328. Its totient is φ = 20690520.

The previous prime is 21035401. The next prime is 21035429. The reversal of 21035423 is 32453012.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 21035423 - 2⁶ = 21035359 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21035395 and 21035404.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21035429) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 172361 + ... + 172482.

It is an arithmetic number, because the mean of its divisors is an integer number (5345082).

Almost surely, 2^21035423 is an apocalyptic number.

21035423 is a deficient number, since it is larger than the sum of its proper divisors (344905).

21035423 is an equidigital number, since it uses as much as digits as its factorization.

21035423 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 344904.

The product of its (nonzero) digits is 720, while the sum is 20.

The square root of 21035423 is about 4586.4390326265. The cubic root of 21035423 is about 276.0474564830.

Adding to 21035423 its reverse (32453012), we get a palindrome (53488435).

The spelling of 21035423 in words is "twenty-one million, thirty-five thousand, four hundred twenty-three".