21741644 has 24 divisors (see below), whose sum is σ = 40040448. Its totient is φ = 10316160.

The previous prime is 21741641. The next prime is 21741649. The reversal of 21741644 is 44614712.

It is a happy number.

It is not an unprimeable number, because it can be changed into a prime (21741641) 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, 4277 + ... + 7859.

It is an arithmetic number, because the mean of its divisors is an integer number (1668352).

Almost surely, 2^21741644 is an apocalyptic number.

It is an amenable number.

21741644 is a deficient number, since it is larger than the sum of its proper divisors (18298804).

21741644 is a wasteful number, since it uses less digits than its factorization.

21741644 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3665 (or 3663 counting only the distinct ones).

The product of its digits is 5376, while the sum is 29.

The square root of 21741644 is about 4662.7935832503. The cubic root of 21741644 is about 279.1027571631.

The spelling of 21741644 in words is "twenty-one million, seven hundred forty-one thousand, six hundred forty-four".