21653463 has 12 divisors (see below), whose sum is σ = 31263720. Its totient is φ = 13324896.

The previous prime is 21653449. The next prime is 21653497. The reversal of 21653463 is 36435612.

It is not a de Polignac number, because 21653463 - 2⁴ = 21653447 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21653463.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21653063) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 20848 + ... + 21861.

It is an arithmetic number, because the mean of its divisors is an integer number (2605310).

Almost surely, 2^21653463 is an apocalyptic number.

21653463 is a deficient number, since it is larger than the sum of its proper divisors (9610257).

21653463 is a wasteful number, since it uses less digits than its factorization.

21653463 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 42738 (or 42725 counting only the distinct ones).

The product of its digits is 12960, while the sum is 30.

The square root of 21653463 is about 4653.3281637985. The cubic root of 21653463 is about 278.7249122454.

The spelling of 21653463 in words is "twenty-one million, six hundred fifty-three thousand, four hundred sixty-three".