21127020 has 48 divisors (see below), whose sum is σ = 59458560. Its totient is φ = 5605056.

The previous prime is 21127009. The next prime is 21127021. The reversal of 21127020 is 2072112.

It is a Harshad number since it is a multiple of its sum of digits (15).

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, 12591 + ... + 14169.

It is an arithmetic number, because the mean of its divisors is an integer number (1238720).

Almost surely, 2^21127020 is an apocalyptic number.

21127020 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21127020 is an abundant number, since it is smaller than the sum of its proper divisors (38331540).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21127020 is a wasteful number, since it uses less digits than its factorization.

21127020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1814 (or 1812 counting only the distinct ones).

The product of its (nonzero) digits is 56, while the sum is 15.

The square root of 21127020 is about 4596.4138194901. The cubic root of 21127020 is about 276.4475515472.

Adding to 21127020 its reverse (2072112), we get a palindrome (23199132).

The spelling of 21127020 in words is "twenty-one million, one hundred twenty-seven thousand, twenty".