21011020466 has 24 divisors (see below), whose sum is σ = 32571076356. Its totient is φ = 10164864960.

The previous prime is 21011020451. The next prime is 21011020489. The reversal of 21011020466 is 66402011012.

It can be written as a sum of positive squares in 6 ways, for example, as 13928956441 + 7082064025 = 118021^2 + 84155^2 .

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 474380 + ... + 516776.

Almost surely, 2^21011020466 is an apocalyptic number.

21011020466 is a deficient number, since it is larger than the sum of its proper divisors (11560055890).

21011020466 is a wasteful number, since it uses less digits than its factorization.

21011020466 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 42654 (or 42617 counting only the distinct ones).

The product of its (nonzero) digits is 576, while the sum is 23.

Adding to 21011020466 its reverse (66402011012), we get a palindrome (87413031478).

The spelling of 21011020466 in words is "twenty-one billion, eleven million, twenty thousand, four hundred sixty-six".