21133403 has 2 divisors, whose sum is σ = 21133404. Its totient is φ = 21133402.

The previous prime is 21133381. The next prime is 21133423. The reversal of 21133403 is 30433112.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21133403 - 2¹⁶ = 21067867 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (21133423) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10566701 + 10566702.

It is an arithmetic number, because the mean of its divisors is an integer number (10566702).

Almost surely, 2^21133403 is an apocalyptic number.

21133403 is a deficient number, since it is larger than the sum of its proper divisors (1).

21133403 is an equidigital number, since it uses as much as digits as its factorization.

21133403 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 216, while the sum is 17.

The square root of 21133403 is about 4597.1081127161. The cubic root of 21133403 is about 276.4753893121.

Adding to 21133403 its reverse (30433112), we get a palindrome (51566515).

The spelling of 21133403 in words is "twenty-one million, one hundred thirty-three thousand, four hundred three".