21420121003 has 2 divisors, whose sum is σ = 21420121004. Its totient is φ = 21420121002.

The previous prime is 21420120983. The next prime is 21420121039. The reversal of 21420121003 is 30012102412.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21420121003 - 2¹⁷ = 21419989931 is a prime.

It is a super-3 number, since 3×21420121003³ (a number of 32 digits) contains 333 as substring.

It is not a weakly prime, because it can be changed into another prime (21420121403) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10710060501 + 10710060502.

It is an arithmetic number, because the mean of its divisors is an integer number (10710060502).

Almost surely, 2^21420121003 is an apocalyptic number.

21420121003 is a deficient number, since it is larger than the sum of its proper divisors (1).

21420121003 is an equidigital number, since it uses as much as digits as its factorization.

21420121003 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 96, while the sum is 16.

Adding to 21420121003 its reverse (30012102412), we get a palindrome (51432223415).

It can be divided in two parts, 21 and 420121003, that added together give a palindrome (420121024).

The spelling of 21420121003 in words is "twenty-one billion, four hundred twenty million, one hundred twenty-one thousand, three".