21127051 has 16 divisors (see below), whose sum is σ = 24111360. Its totient is φ = 18335520.

The previous prime is 21127033. The next prime is 21127081. The reversal of 21127051 is 15072112.

It is a cyclic number.

It is not a de Polignac number, because 21127051 - 2¹¹ = 21125003 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21127021) by changing a digit.

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 in 15 ways as a sum of consecutive naturals, for example, 32536 + ... + 33178.

It is an arithmetic number, because the mean of its divisors is an integer number (1506960).

Almost surely, 2^21127051 is an apocalyptic number.

21127051 is a deficient number, since it is larger than the sum of its proper divisors (2984309).

21127051 is a wasteful number, since it uses less digits than its factorization.

21127051 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 786.

The product of its (nonzero) digits is 140, while the sum is 19.

The square root of 21127051 is about 4596.4171916831. The cubic root of 21127051 is about 276.4476867590.

Adding to 21127051 its reverse (15072112), we get a palindrome (36199163).

The spelling of 21127051 in words is "twenty-one million, one hundred twenty-seven thousand, fifty-one".