21030003251 has 2 divisors, whose sum is σ = 21030003252. Its totient is φ = 21030003250.

The previous prime is 21030003233. The next prime is 21030003271. The reversal of 21030003251 is 15230003012.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21030003251 - 2¹⁸ = 21029741107 is a prime.

It is a super-2 number, since 2×21030003251² (a number of 21 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (21030003271) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10515001625 + 10515001626.

It is an arithmetic number, because the mean of its divisors is an integer number (10515001626).

Almost surely, 2^21030003251 is an apocalyptic number.

21030003251 is a deficient number, since it is larger than the sum of its proper divisors (1).

21030003251 is an equidigital number, since it uses as much as digits as its factorization.

21030003251 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 180, while the sum is 17.

Adding to 21030003251 its reverse (15230003012), we get a palindrome (36260006263).

The spelling of 21030003251 in words is "twenty-one billion, thirty million, three thousand, two hundred fifty-one".