21067331 has 2 divisors, whose sum is σ = 21067332. Its totient is φ = 21067330.

The previous prime is 21067303. The next prime is 21067349. The reversal of 21067331 is 13376012.

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-21067331 is a prime.

It is a super-2 number, since 2×21067331² = 887664870927122, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21067297 and 21067306.

It is not a weakly prime, because it can be changed into another prime (21067391) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10533665 + 10533666.

It is an arithmetic number, because the mean of its divisors is an integer number (10533666).

Almost surely, 2^21067331 is an apocalyptic number.

21067331 is a deficient number, since it is larger than the sum of its proper divisors (1).

21067331 is an equidigital number, since it uses as much as digits as its factorization.

21067331 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 756, while the sum is 23.

The square root of 21067331 is about 4589.9162301724. The cubic root of 21067331 is about 276.1869619955.

The spelling of 21067331 in words is "twenty-one million, sixty-seven thousand, three hundred thirty-one".