21014644 has 24 divisors (see below), whose sum is σ = 42146048. Its totient is φ = 8981280.

The previous prime is 21014641. The next prime is 21014657. The reversal of 21014644 is 44641012.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21014641) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 12154 + ... + 13774.

Almost surely, 2^21014644 is an apocalyptic number.

It is an amenable number.

21014644 is an abundant number, since it is smaller than the sum of its proper divisors (21131404).

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

21014644 is a wasteful number, since it uses less digits than its factorization.

21014644 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2095 (or 2093 counting only the distinct ones).

The product of its (nonzero) digits is 768, while the sum is 22.

The square root of 21014644 is about 4584.1732078969. The cubic root of 21014644 is about 275.9565323970.

Adding to 21014644 its reverse (44641012), we get a palindrome (65655656).

The spelling of 21014644 in words is "twenty-one million, fourteen thousand, six hundred forty-four".