21127882 has 4 divisors (see below), whose sum is σ = 31691826. Its totient is φ = 10563940.

The previous prime is 21127877. The next prime is 21127901. The reversal of 21127882 is 28872112.

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., 15515721 + 5612161 = 3939^2 + 2369^2 .

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5281969 + ... + 5281972.

Almost surely, 2^21127882 is an apocalyptic number.

21127882 is a deficient number, since it is larger than the sum of its proper divisors (10563944).

21127882 is a wasteful number, since it uses less digits than its factorization.

21127882 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10563943.

The product of its digits is 3584, while the sum is 31.

The square root of 21127882 is about 4596.5075872884. The cubic root of 21127882 is about 276.4513112595.

Adding to 21127882 its reverse (28872112), we get a palindrome (49999994).

The spelling of 21127882 in words is "twenty-one million, one hundred twenty-seven thousand, eight hundred eighty-two".