21003000671 has 2 divisors, whose sum is σ = 21003000672. Its totient is φ = 21003000670.

The previous prime is 21003000661. The next prime is 21003000677. The reversal of 21003000671 is 17600030012.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21003000671 - 2²⁶ = 20935891807 is a prime.

It is a super-3 number, since 3×21003000671³ (a number of 32 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21003000677) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10501500335 + 10501500336.

It is an arithmetic number, because the mean of its divisors is an integer number (10501500336).

Almost surely, 2^21003000671 is an apocalyptic number.

21003000671 is a deficient number, since it is larger than the sum of its proper divisors (1).

21003000671 is an equidigital number, since it uses as much as digits as its factorization.

21003000671 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 252, while the sum is 20.

Adding to 21003000671 its reverse (17600030012), we get a palindrome (38603030683).

The spelling of 21003000671 in words is "twenty-one billion, three million, six hundred seventy-one", and thus it is an aban number.