21458016 has 36 divisors (see below), whose sum is σ = 61022052. Its totient is φ = 7152576.

The previous prime is 21458009. The next prime is 21458027. The reversal of 21458016 is 61085412.

It is a tau number, because it is divible by the number of its divisors (36).

It is a congruent number.

It is an unprimeable number.

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 5 ways as a sum of consecutive naturals, for example, 36966 + ... + 37541.

It is an arithmetic number, because the mean of its divisors is an integer number (1695057).

Almost surely, 2^21458016 is an apocalyptic number.

It is an amenable number.

21458016 is an abundant number, since it is smaller than the sum of its proper divisors (39564036).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21458016 is a wasteful number, since it uses less digits than its factorization.

21458016 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 74523 (or 74512 counting only the distinct ones).

The product of its (nonzero) digits is 1920, while the sum is 27.

The square root of 21458016 is about 4632.2797842963. The cubic root of 21458016 is about 277.8837738534.

The spelling of 21458016 in words is "twenty-one million, four hundred fifty-eight thousand, sixteen".