21820703 has 2 divisors, whose sum is σ = 21820704. Its totient is φ = 21820702.

The previous prime is 21820699. The next prime is 21820709. The reversal of 21820703 is 30702812.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21820703 - 2² = 21820699 is a prime.

It is a super-2 number, since 2×21820703² = 952286158828418, which contains 22 as substring.

It is a Sophie Germain prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21820709) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10910351 + 10910352.

It is an arithmetic number, because the mean of its divisors is an integer number (10910352).

Almost surely, 2^21820703 is an apocalyptic number.

21820703 is a deficient number, since it is larger than the sum of its proper divisors (1).

21820703 is an equidigital number, since it uses as much as digits as its factorization.

21820703 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 672, while the sum is 23.

The square root of 21820703 is about 4671.2635335635. The cubic root of 21820703 is about 279.4406477895.

The spelling of 21820703 in words is "twenty-one million, eight hundred twenty thousand, seven hundred three".