21004022 has 16 divisors (see below), whose sum is σ = 34202112. Its totient is φ = 9616320.

The previous prime is 21003937. The next prime is 21004043. The reversal of 21004022 is 22040012.

It is a junction number, because it is equal to n+sod(n) for n = 21003994 and 21004012.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 122 + ... + 6482.

It is an arithmetic number, because the mean of its divisors is an integer number (2137632).

Almost surely, 2^21004022 is an apocalyptic number.

21004022 is a deficient number, since it is larger than the sum of its proper divisors (13198090).

21004022 is a wasteful number, since it uses less digits than its factorization.

21004022 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6503.

The product of its (nonzero) digits is 32, while the sum is 11.

The square root of 21004022 is about 4583.0145101232. The cubic root of 21004022 is about 275.9100298361.

Adding to 21004022 its reverse (22040012), we get a palindrome (43044034).

The spelling of 21004022 in words is "twenty-one million, four thousand, twenty-two".