21330538571 has 16 divisors (see below), whose sum is σ = 22745219904. Its totient is φ = 19933814784.

The previous prime is 21330538553. The next prime is 21330538601. The reversal of 21330538571 is 17583503312.

It is a cyclic number.

It is not a de Polignac number, because 21330538571 - 2¹⁸ = 21330276427 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21330538511) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 7346306 + ... + 7349208.

It is an arithmetic number, because the mean of its divisors is an integer number (1421576244).

Almost surely, 2^21330538571 is an apocalyptic number.

21330538571 is a deficient number, since it is larger than the sum of its proper divisors (1414681333).

21330538571 is a wasteful number, since it uses less digits than its factorization.

21330538571 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5830.

The product of its (nonzero) digits is 75600, while the sum is 38.

The spelling of 21330538571 in words is "twenty-one billion, three hundred thirty million, five hundred thirty-eight thousand, five hundred seventy-one".