21221766703 has 2 divisors, whose sum is σ = 21221766704. Its totient is φ = 21221766702.

The previous prime is 21221766659. The next prime is 21221766721. The reversal of 21221766703 is 30766712212.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21221766703 - 2²¹ = 21219669551 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21221766743) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10610883351 + 10610883352.

It is an arithmetic number, because the mean of its divisors is an integer number (10610883352).

Almost surely, 2^21221766703 is an apocalyptic number.

21221766703 is a deficient number, since it is larger than the sum of its proper divisors (1).

21221766703 is an equidigital number, since it uses as much as digits as its factorization.

21221766703 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 42336, while the sum is 37.

The spelling of 21221766703 in words is "twenty-one billion, two hundred twenty-one million, seven hundred sixty-six thousand, seven hundred three".