21967633 has 2 divisors, whose sum is σ = 21967634. Its totient is φ = 21967632.

The previous prime is 21967619. The next prime is 21967637. The reversal of 21967633 is 33676912.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 16265089 + 5702544 = 4033^2 + 2388^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21967633 is a prime.

It is a plaindrome in base 15.

It is a junction number, because it is equal to n+sod(n) for n = 21967592 and 21967601.

It is not a weakly prime, because it can be changed into another prime (21967637) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10983816 + 10983817.

It is an arithmetic number, because the mean of its divisors is an integer number (10983817).

Almost surely, 2^21967633 is an apocalyptic number.

It is an amenable number.

21967633 is a deficient number, since it is larger than the sum of its proper divisors (1).

21967633 is an equidigital number, since it uses as much as digits as its factorization.

21967633 is an evil number, because the sum of its binary digits is even.

The product of its digits is 40824, while the sum is 37.

The square root of 21967633 is about 4686.9641560396. The cubic root of 21967633 is about 280.0664510650.

The spelling of 21967633 in words is "twenty-one million, nine hundred sixty-seven thousand, six hundred thirty-three".