21076420 has 12 divisors (see below), whose sum is σ = 44260524. Its totient is φ = 8430560.

The previous prime is 21076411. The next prime is 21076423. The reversal of 21076420 is 2467012.

It can be written as a sum of positive squares in 2 ways, for example, as 9132484 + 11943936 = 3022^2 + 3456^2 .

It is a junction number, because it is equal to n+sod(n) for n = 21076391 and 21076400.

It is not an unprimeable number, because it can be changed into a prime (21076423) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 526891 + ... + 526930.

It is an arithmetic number, because the mean of its divisors is an integer number (3688377).

Almost surely, 2^21076420 is an apocalyptic number.

21076420 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21076420 is an abundant number, since it is smaller than the sum of its proper divisors (23184104).

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

21076420 is a wasteful number, since it uses less digits than its factorization.

21076420 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1053830 (or 1053828 counting only the distinct ones).

The product of its (nonzero) digits is 672, while the sum is 22.

The square root of 21076420 is about 4590.9062286220. The cubic root of 21076420 is about 276.2266743885.

The spelling of 21076420 in words is "twenty-one million, seventy-six thousand, four hundred twenty".