21404034 has 32 divisors (see below), whose sum is σ = 47715840. Its totient is φ = 7112016.

The previous prime is 21404029. The next prime is 21404063. The reversal of 21404034 is 43040412.

It is a super-3 number, since 3×21404034³ (a number of 23 digits) contains 333 as substring.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 21403998 and 21404016.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 32452 + ... + 33104.

It is an arithmetic number, because the mean of its divisors is an integer number (1491120).

Almost surely, 2^21404034 is an apocalyptic number.

21404034 is an abundant number, since it is smaller than the sum of its proper divisors (26311806).

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

21404034 is a wasteful number, since it uses less digits than its factorization.

21404034 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1271 (or 1265 counting only the distinct ones).

The product of its (nonzero) digits is 384, while the sum is 18.

The square root of 21404034 is about 4626.4493945141. The cubic root of 21404034 is about 277.6505538047.

Adding to 21404034 its reverse (43040412), we get a palindrome (64444446).

The spelling of 21404034 in words is "twenty-one million, four hundred four thousand, thirty-four".