21453807 has 8 divisors (see below), whose sum is σ = 28626480. Its totient is φ = 14291840.

The previous prime is 21453799. The next prime is 21453833. The reversal of 21453807 is 70835412.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21453807 - 2³ = 21453799 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21453877) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 6457 + ... + 9197.

It is an arithmetic number, because the mean of its divisors is an integer number (3578310).

Almost surely, 2^21453807 is an apocalyptic number.

21453807 is a deficient number, since it is larger than the sum of its proper divisors (7172673).

21453807 is a wasteful number, since it uses less digits than its factorization.

21453807 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5353.

The product of its (nonzero) digits is 6720, while the sum is 30.

The square root of 21453807 is about 4631.8254500791. The cubic root of 21453807 is about 277.8656036541.

The spelling of 21453807 in words is "twenty-one million, four hundred fifty-three thousand, eight hundred seven".