21131122 has 4 divisors (see below), whose sum is σ = 31696686. Its totient is φ = 10565560.

The previous prime is 21131087. The next prime is 21131137. The reversal of 21131122 is 22113112.

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., 11895601 + 9235521 = 3449^2 + 3039^2 .

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, 5282779 + ... + 5282782.

Almost surely, 2^21131122 is an apocalyptic number.

21131122 is a deficient number, since it is larger than the sum of its proper divisors (10565564).

21131122 is a wasteful number, since it uses less digits than its factorization.

21131122 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10565563.

The product of its digits is 24, while the sum is 13.

The square root of 21131122 is about 4596.8600152713. The cubic root of 21131122 is about 276.4654419781.

Adding to 21131122 its reverse (22113112), we get a palindrome (43244234).

It can be divided in two parts, 2113112 and 2, that multiplied together give a palindrome (4226224).

The spelling of 21131122 in words is "twenty-one million, one hundred thirty-one thousand, one hundred twenty-two".