21134021 has 2 divisors, whose sum is σ = 21134022. Its totient is φ = 21134020.

The previous prime is 21133979. The next prime is 21134063. The reversal of 21134021 is 12043112.

It is a balanced prime because it is at equal distance from previous prime (21133979) and next prime (21134063).

It can be written as a sum of positive squares in only one way, i.e., 10797796 + 10336225 = 3286^2 + 3215^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21134021 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21133987 and 21134005.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21134081) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10567010 + 10567011.

It is an arithmetic number, because the mean of its divisors is an integer number (10567011).

Almost surely, 2^21134021 is an apocalyptic number.

It is an amenable number.

21134021 is a deficient number, since it is larger than the sum of its proper divisors (1).

21134021 is an equidigital number, since it uses as much as digits as its factorization.

21134021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 48, while the sum is 14.

The square root of 21134021 is about 4597.1753283946. The cubic root of 21134021 is about 276.4780842578.

Adding to 21134021 its reverse (12043112), we get a palindrome (33177133).

Subtracting from 21134021 its reverse (12043112), we obtain a palindrome (9090909).

The spelling of 21134021 in words is "twenty-one million, one hundred thirty-four thousand, twenty-one".