10840021 has 2 divisors, whose sum is σ = 10840022. Its totient is φ = 10840020.

The previous prime is 10840009. The next prime is 10840057. The reversal of 10840021 is 12004801.

It is a happy number.

10840021 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 10817521 + 22500 = 3289^2 + 150^2 .

It is an emirp because it is prime and its reverse (12004801) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 10840021 - 2¹¹ = 10837973 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 10839977 and 10840004.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (10840091) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5420010 + 5420011.

It is an arithmetic number, because the mean of its divisors is an integer number (5420011).

Almost surely, 2^10840021 is an apocalyptic number.

It is an amenable number.

10840021 is a deficient number, since it is larger than the sum of its proper divisors (1).

10840021 is an equidigital number, since it uses as much as digits as its factorization.

10840021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 64, while the sum is 16.

The square root of 10840021 is about 3292.4187157772. The cubic root of 10840021 is about 221.3145878444.

Adding to 10840021 its reverse (12004801), we get a palindrome (22844822).

The spelling of 10840021 in words is "ten million, eight hundred forty thousand, twenty-one".