21127701 has 16 divisors (see below), whose sum is σ = 32269824. Its totient is φ = 12044784.

The previous prime is 21127699. The next prime is 21127721. The reversal of 21127701 is 10772112.

It is a happy number.

It is not a de Polignac number, because 21127701 - 2¹ = 21127699 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21127721) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 10930 + ... + 12716.

It is an arithmetic number, because the mean of its divisors is an integer number (2016864).

Almost surely, 2^21127701 is an apocalyptic number.

21127701 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

21127701 is a deficient number, since it is larger than the sum of its proper divisors (11142123).

21127701 is a wasteful number, since it uses less digits than its factorization.

21127701 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2360.

The product of its (nonzero) digits is 196, while the sum is 21.

The square root of 21127701 is about 4596.4878983850. The cubic root of 21127701 is about 276.4505218156.

Adding to 21127701 its reverse (10772112), we get a palindrome (31899813).

The spelling of 21127701 in words is "twenty-one million, one hundred twenty-seven thousand, seven hundred one".