21021146 has 8 divisors (see below), whose sum is σ = 33386580. Its totient is φ = 9892288.

The previous prime is 21021127. The next prime is 21021157. The reversal of 21021146 is 64112012.

It can be written as a sum of positive squares in 2 ways, for example, as 19228225 + 1792921 = 4385^2 + 1339^2 .

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

It is a Harshad number since it is a multiple of its sum of digits (17).

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 309101 + ... + 309168.

Almost surely, 2^21021146 is an apocalyptic number.

21021146 is a deficient number, since it is larger than the sum of its proper divisors (12365434).

21021146 is a wasteful number, since it uses less digits than its factorization.

21021146 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 618288.

The product of its (nonzero) digits is 96, while the sum is 17.

The square root of 21021146 is about 4584.8823321869. The cubic root of 21021146 is about 275.9849900820.

Adding to 21021146 its reverse (64112012), we get a palindrome (85133158).

The spelling of 21021146 in words is "twenty-one million, twenty-one thousand, one hundred forty-six".