21057000271 has 2 divisors, whose sum is σ = 21057000272. Its totient is φ = 21057000270.

The previous prime is 21057000247. The next prime is 21057000277. The reversal of 21057000271 is 17200075012.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21057000271 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21057000277) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10528500135 + 10528500136.

It is an arithmetic number, because the mean of its divisors is an integer number (10528500136).

Almost surely, 2^21057000271 is an apocalyptic number.

21057000271 is a deficient number, since it is larger than the sum of its proper divisors (1).

21057000271 is an equidigital number, since it uses as much as digits as its factorization.

21057000271 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 980, while the sum is 25.

Adding to 21057000271 its reverse (17200075012), we get a palindrome (38257075283).

The spelling of 21057000271 in words is "twenty-one billion, fifty-seven million, two hundred seventy-one", and thus it is an aban number.