21135346 has 4 divisors (see below), whose sum is σ = 31703022. Its totient is φ = 10567672.

The previous prime is 21135337. The next prime is 21135347. The reversal of 21135346 is 64353112.

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., 19018321 + 2117025 = 4361^2 + 1455^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 21135346.

It is not an unprimeable number, because it can be changed into a prime (21135347) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5283835 + ... + 5283838.

Almost surely, 2^21135346 is an apocalyptic number.

21135346 is a deficient number, since it is larger than the sum of its proper divisors (10567676).

21135346 is a wasteful number, since it uses less digits than its factorization.

21135346 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10567675.

The product of its digits is 2160, while the sum is 25.

The square root of 21135346 is about 4597.3194363672. The cubic root of 21135346 is about 276.4838620794.

Adding to 21135346 its reverse (64353112), we get a palindrome (85488458).

The spelling of 21135346 in words is "twenty-one million, one hundred thirty-five thousand, three hundred forty-six".