21127798 has 16 divisors (see below), whose sum is σ = 32134320. Its totient is φ = 10417696.

The previous prime is 21127783. The next prime is 21127817. The reversal of 21127798 is 89772112.

It is a super-3 number, since 3×21127798³ (a number of 23 digits) contains 333 as substring.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 78408 + ... + 78676.

It is an arithmetic number, because the mean of its divisors is an integer number (2008395).

Almost surely, 2^21127798 is an apocalyptic number.

21127798 is a deficient number, since it is larger than the sum of its proper divisors (11006522).

21127798 is a wasteful number, since it uses less digits than its factorization.

21127798 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 671.

The product of its digits is 14112, while the sum is 37.

The square root of 21127798 is about 4596.4984499073. The cubic root of 21127798 is about 276.4509448883.

The spelling of 21127798 in words is "twenty-one million, one hundred twenty-seven thousand, seven hundred ninety-eight".