21452881 has 8 divisors (see below), whose sum is σ = 23133600. Its totient is φ = 19827360.

The previous prime is 21452867. The next prime is 21452887. The reversal of 21452881 is 18825412.

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 21452881 - 2¹⁷ = 21321809 is a prime.

It is a super-2 number, since 2×21452881² = 920452206400322, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21452887) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 12991 + ... + 14548.

It is an arithmetic number, because the mean of its divisors is an integer number (2891700).

Almost surely, 2^21452881 is an apocalyptic number.

It is an amenable number.

21452881 is a deficient number, since it is larger than the sum of its proper divisors (1680719).

21452881 is a wasteful number, since it uses less digits than its factorization.

21452881 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 27599.

The product of its digits is 5120, while the sum is 31.

The square root of 21452881 is about 4631.7254884114. The cubic root of 21452881 is about 277.8616058049.

The spelling of 21452881 in words is "twenty-one million, four hundred fifty-two thousand, eight hundred eighty-one".