21111211003 has 2 divisors, whose sum is σ = 21111211004. Its totient is φ = 21111211002.

The previous prime is 21111210977. The next prime is 21111211013. The reversal of 21111211003 is 30011211112.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21111211003 - 2⁵ = 21111210971 is a prime.

It is not a weakly prime, because it can be changed into another prime (21111211013) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10555605501 + 10555605502.

It is an arithmetic number, because the mean of its divisors is an integer number (10555605502).

Almost surely, 2^21111211003 is an apocalyptic number.

21111211003 is a deficient number, since it is larger than the sum of its proper divisors (1).

21111211003 is an equidigital number, since it uses as much as digits as its factorization.

21111211003 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 12, while the sum is 13.

Adding to 21111211003 its reverse (30011211112), we get a palindrome (51122422115).

The spelling of 21111211003 in words is "twenty-one billion, one hundred eleven million, two hundred eleven thousand, three".