21612034 has 4 divisors (see below), whose sum is σ = 32418054. Its totient is φ = 10806016.

The previous prime is 21612023. The next prime is 21612037. The reversal of 21612034 is 43021612.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 18361225 + 3250809 = 4285^2 + 1803^2 .

It is not an unprimeable number, because it can be changed into a prime (21612037) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5403007 + ... + 5403010.

Almost surely, 2^21612034 is an apocalyptic number.

21612034 is a deficient number, since it is larger than the sum of its proper divisors (10806020).

21612034 is a wasteful number, since it uses less digits than its factorization.

21612034 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10806019.

The product of its (nonzero) digits is 288, while the sum is 19.

The square root of 21612034 is about 4648.8744874432. The cubic root of 21612034 is about 278.5470397483.

Adding to 21612034 its reverse (43021612), we get a palindrome (64633646).

The spelling of 21612034 in words is "twenty-one million, six hundred twelve thousand, thirty-four".