21612046 has 4 divisors (see below), whose sum is σ = 32418072. Its totient is φ = 10806022.

The previous prime is 21612037. The next prime is 21612061. The reversal of 21612046 is 64021612.

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

It is a super-2 number, since 2×21612046² = 934161064612232, which contains 22 as substring.

It is a Smith number, since the sum of its digits (22) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5403010 + ... + 5403013.

It is an arithmetic number, because the mean of its divisors is an integer number (8104518).

Almost surely, 2^21612046 is an apocalyptic number.

21612046 is a deficient number, since it is larger than the sum of its proper divisors (10806026).

21612046 is a wasteful number, since it uses less digits than its factorization.

21612046 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10806025.

The product of its (nonzero) digits is 576, while the sum is 22.

The square root of 21612046 is about 4648.8757780780. The cubic root of 21612046 is about 278.5470913024.

Adding to 21612046 its reverse (64021612), we get a palindrome (85633658).

The spelling of 21612046 in words is "twenty-one million, six hundred twelve thousand, forty-six".