21040530465 has 16 divisors (see below), whose sum is σ = 33698843136. Its totient is φ = 11210284800.

The previous prime is 21040530463. The next prime is 21040530481. The reversal of 21040530465 is 56403504012.

It is not a de Polignac number, because 21040530465 - 2¹ = 21040530463 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21040530463) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 692856 + ... + 722585.

It is an arithmetic number, because the mean of its divisors is an integer number (2106177696).

Almost surely, 2^21040530465 is an apocalyptic number.

It is an amenable number.

21040530465 is a deficient number, since it is larger than the sum of its proper divisors (12658312671).

21040530465 is a wasteful number, since it uses less digits than its factorization.

21040530465 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1416440.

The product of its (nonzero) digits is 14400, while the sum is 30.

The spelling of 21040530465 in words is "twenty-one billion, forty million, five hundred thirty thousand, four hundred sixty-five".