21034571 has 2 divisors, whose sum is σ = 21034572. Its totient is φ = 21034570.

The previous prime is 21034567. The next prime is 21034591. The reversal of 21034571 is 17543012.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21034571 - 2² = 21034567 is a prime.

It is not a weakly prime, because it can be changed into another prime (21034561) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10517285 + 10517286.

It is an arithmetic number, because the mean of its divisors is an integer number (10517286).

Almost surely, 2^21034571 is an apocalyptic number.

21034571 is a deficient number, since it is larger than the sum of its proper divisors (1).

21034571 is an equidigital number, since it uses as much as digits as its factorization.

21034571 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 840, while the sum is 23.

The square root of 21034571 is about 4586.3461491693. The cubic root of 21034571 is about 276.0437295060.

Adding to 21034571 its reverse (17543012), we get a palindrome (38577583).

The spelling of 21034571 in words is "twenty-one million, thirty-four thousand, five hundred seventy-one".