21135046 has 8 divisors (see below), whose sum is σ = 33567480. Its totient is φ = 9945888.

The previous prime is 21135041. The next prime is 21135047. The reversal of 21135046 is 64053112.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21135041) 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 3 ways as a sum of consecutive naturals, for example, 310776 + ... + 310843.

It is an arithmetic number, because the mean of its divisors is an integer number (4195935).

Almost surely, 2^21135046 is an apocalyptic number.

21135046 is a deficient number, since it is larger than the sum of its proper divisors (12432434).

21135046 is a wasteful number, since it uses less digits than its factorization.

21135046 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 621638.

The product of its (nonzero) digits is 720, while the sum is 22.

The square root of 21135046 is about 4597.2868085426. The cubic root of 21135046 is about 276.4825539145.

Adding to 21135046 its reverse (64053112), we get a palindrome (85188158).

The spelling of 21135046 in words is "twenty-one million, one hundred thirty-five thousand, forty-six".