21352658 has 4 divisors (see below), whose sum is σ = 32028990. Its totient is φ = 10676328.

The previous prime is 21352651. The next prime is 21352687. The reversal of 21352658 is 85625312.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 15626209 + 5726449 = 3953^2 + 2393^2 .

It is not an unprimeable number, because it can be changed into a prime (21352651) 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 as a sum of consecutive naturals, namely, 5338163 + ... + 5338166.

Almost surely, 2^21352658 is an apocalyptic number.

21352658 is a deficient number, since it is larger than the sum of its proper divisors (10676332).

21352658 is a wasteful number, since it uses less digits than its factorization.

21352658 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10676331.

The product of its digits is 14400, while the sum is 32.

The square root of 21352658 is about 4620.8936365166. The cubic root of 21352658 is about 277.4282280637.

The spelling of 21352658 in words is "twenty-one million, three hundred fifty-two thousand, six hundred fifty-eight".