21445652 has 6 divisors (see below), whose sum is σ = 37529898. Its totient is φ = 10722824.

The previous prime is 21445651. The next prime is 21445657. The reversal of 21445652 is 25654412.

It can be written as a sum of positive squares in only one way, i.e., 20921476 + 524176 = 4574^2 + 724^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21445651) by changing a digit.

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, 2680703 + ... + 2680710.

It is an arithmetic number, because the mean of its divisors is an integer number (6254983).

Almost surely, 2^21445652 is an apocalyptic number.

It is an amenable number.

21445652 is a deficient number, since it is larger than the sum of its proper divisors (16084246).

21445652 is a wasteful number, since it uses less digits than its factorization.

21445652 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5361417 (or 5361415 counting only the distinct ones).

The product of its digits is 9600, while the sum is 29.

The square root of 21445652 is about 4630.9450439408. The cubic root of 21445652 is about 277.8303918589.

The spelling of 21445652 in words is "twenty-one million, four hundred forty-five thousand, six hundred fifty-two".