21151322 has 4 divisors (see below), whose sum is σ = 31726986. Its totient is φ = 10575660.

The previous prime is 21151307. The next prime is 21151343. The reversal of 21151322 is 22315112.

It is a happy number.

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., 17732521 + 3418801 = 4211^2 + 1849^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 21151322.

It is an unprimeable number.

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 as a sum of consecutive naturals, namely, 5287829 + ... + 5287832.

Almost surely, 2^21151322 is an apocalyptic number.

21151322 is a deficient number, since it is larger than the sum of its proper divisors (10575664).

21151322 is a wasteful number, since it uses less digits than its factorization.

21151322 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10575663.

The product of its digits is 120, while the sum is 17.

The square root of 21151322 is about 4599.0566423996. The cubic root of 21151322 is about 276.5535083440.

Adding to 21151322 its reverse (22315112), we get a palindrome (43466434).

The spelling of 21151322 in words is "twenty-one million, one hundred fifty-one thousand, three hundred twenty-two".