21970363 has 2 divisors, whose sum is σ = 21970364. Its totient is φ = 21970362.

The previous prime is 21970339. The next prime is 21970369. The reversal of 21970363 is 36307912.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21970363 is a prime.

It is not a weakly prime, because it can be changed into another prime (21970369) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10985181 + 10985182.

It is an arithmetic number, because the mean of its divisors is an integer number (10985182).

Almost surely, 2^21970363 is an apocalyptic number.

21970363 is a deficient number, since it is larger than the sum of its proper divisors (1).

21970363 is an equidigital number, since it uses as much as digits as its factorization.

21970363 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 6804, while the sum is 31.

The square root of 21970363 is about 4687.2553802839. The cubic root of 21970363 is about 280.0780522199.

The spelling of 21970363 in words is "twenty-one million, nine hundred seventy thousand, three hundred sixty-three".