21204034 has 8 divisors (see below), whose sum is σ = 32665788. Its totient is φ = 10315440.

The previous prime is 21204013. The next prime is 21204037. The reversal of 21204034 is 43040212.

It can be written as a sum of positive squares in 2 ways, for example, as 18792225 + 2411809 = 4335^2 + 1553^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a super-2 number, since 2×21204034² = 899222115746312, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21203999 and 21204017.

It is not an unprimeable number, because it can be changed into a prime (21204037) 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, 143197 + ... + 143344.

Almost surely, 2^21204034 is an apocalyptic number.

21204034 is a deficient number, since it is larger than the sum of its proper divisors (11461754).

21204034 is a wasteful number, since it uses less digits than its factorization.

21204034 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 286580.

The product of its (nonzero) digits is 192, while the sum is 16.

The square root of 21204034 is about 4604.7838168583. The cubic root of 21204034 is about 276.7830542072.

Adding to 21204034 its reverse (43040212), we get a palindrome (64244246).

The spelling of 21204034 in words is "twenty-one million, two hundred four thousand, thirty-four".