21628453 has 12 divisors (see below), whose sum is σ = 27447552. Its totient is φ = 16852920.

The previous prime is 21628447. The next prime is 21628459. The reversal of 21628453 is 35482612.

It is an interprime number because it is at equal distance from previous prime (21628447) and next prime (21628459).

It is a de Polignac number, because none of the positive numbers 2^k-21628453 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21628459) 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, 19525 + ... + 20602.

It is an arithmetic number, because the mean of its divisors is an integer number (2287296).

Almost surely, 2^21628453 is an apocalyptic number.

It is an amenable number.

21628453 is a deficient number, since it is larger than the sum of its proper divisors (5819099).

21628453 is a wasteful number, since it uses less digits than its factorization.

21628453 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 40152 (or 40145 counting only the distinct ones).

The product of its digits is 11520, while the sum is 31.

The square root of 21628453 is about 4650.6400634751. The cubic root of 21628453 is about 278.6175607392.

The spelling of 21628453 in words is "twenty-one million, six hundred twenty-eight thousand, four hundred fifty-three".