21489075 has 18 divisors (see below), whose sum is σ = 38489724. Its totient is φ = 11460720.

The previous prime is 21489053. The next prime is 21489077. The reversal of 21489075 is 57098412.

It is not a de Polignac number, because 21489075 - 2⁷ = 21488947 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21489077) by changing a digit.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 47529 + ... + 47978.

It is an arithmetic number, because the mean of its divisors is an integer number (2138318).

Almost surely, 2^21489075 is an apocalyptic number.

21489075 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

21489075 is a deficient number, since it is larger than the sum of its proper divisors (17000649).

21489075 is a wasteful number, since it uses less digits than its factorization.

21489075 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 95523 (or 95515 counting only the distinct ones).

The product of its (nonzero) digits is 20160, while the sum is 36.

The square root of 21489075 is about 4635.6310250062. The cubic root of 21489075 is about 278.0177817586.

The spelling of 21489075 in words is "twenty-one million, four hundred eighty-nine thousand, seventy-five".