21733331 has 2 divisors, whose sum is σ = 21733332. Its totient is φ = 21733330.

The previous prime is 21733307. The next prime is 21733333. The reversal of 21733331 is 13333712.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21733331 is a prime.

It is a super-2 number, since 2×21733331² = 944675352711122, which contains 22 as substring.

Together with 21733333, it forms a pair of twin primes.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 21733297 and 21733306.

It is not a weakly prime, because it can be changed into another prime (21733333) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10866665 + 10866666.

It is an arithmetic number, because the mean of its divisors is an integer number (10866666).

Almost surely, 2^21733331 is an apocalyptic number.

21733331 is a deficient number, since it is larger than the sum of its proper divisors (1).

21733331 is an equidigital number, since it uses as much as digits as its factorization.

21733331 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1134, while the sum is 23.

The square root of 21733331 is about 4661.9020796237. The cubic root of 21733331 is about 279.0671806294.

The spelling of 21733331 in words is "twenty-one million, seven hundred thirty-three thousand, three hundred thirty-one".