21457485 has 48 divisors (see below), whose sum is σ = 45017856. Its totient is φ = 9229824.

The previous prime is 21457481. The next prime is 21457493. The reversal of 21457485 is 58475412.

21457485 is a `hidden beast` number, since 2 + 1 + 4 + 574 + 85 = 666.

It is not a de Polignac number, because 21457485 - 2² = 21457481 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21457481) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 3352 + ... + 7358.

It is an arithmetic number, because the mean of its divisors is an integer number (937872).

Almost surely, 2^21457485 is an apocalyptic number.

It is an amenable number.

21457485 is an abundant number, since it is smaller than the sum of its proper divisors (23560371).

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

21457485 is a wasteful number, since it uses less digits than its factorization.

21457485 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4042 (or 4039 counting only the distinct ones).

The product of its digits is 44800, while the sum is 36.

The square root of 21457485 is about 4632.2224687508. Note that the first 3 decimals coincide. The cubic root of 21457485 is about 277.8814816642.

The spelling of 21457485 in words is "twenty-one million, four hundred fifty-seven thousand, four hundred eighty-five".