21748201 has 2 divisors, whose sum is σ = 21748202. Its totient is φ = 21748200.

The previous prime is 21748171. The next prime is 21748261. The reversal of 21748201 is 10284712.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 13682601 + 8065600 = 3699^2 + 2840^2 .

It is a cyclic number.

It is not a de Polignac number, because 21748201 - 2⁹ = 21747689 is a prime.

It is equal to p_1374316 and since 21748201 and 1374316 have the same sum of digits, it is a Honaker prime.

It is not a weakly prime, because it can be changed into another prime (21748261) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10874100 + 10874101.

It is an arithmetic number, because the mean of its divisors is an integer number (10874101).

Almost surely, 2^21748201 is an apocalyptic number.

It is an amenable number.

21748201 is a deficient number, since it is larger than the sum of its proper divisors (1).

21748201 is an equidigital number, since it uses as much as digits as its factorization.

21748201 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 896, while the sum is 25.

The square root of 21748201 is about 4663.4966495110. The cubic root of 21748201 is about 279.1308122761.

The spelling of 21748201 in words is "twenty-one million, seven hundred forty-eight thousand, two hundred one".