21743701 has 6 divisors (see below), whose sum is σ = 25293750. Its totient is φ = 18637416.

The previous prime is 21743699. The next prime is 21743737. The reversal of 21743701 is 10734712.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 21150801 + 592900 = 4599^2 + 770^2 .

It is not a de Polignac number, because 21743701 - 2¹ = 21743699 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21746701) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 221826 + ... + 221923.

It is an arithmetic number, because the mean of its divisors is an integer number (4215625).

Almost surely, 2^21743701 is an apocalyptic number.

It is an amenable number.

21743701 is a deficient number, since it is larger than the sum of its proper divisors (3550049).

21743701 is an equidigital number, since it uses as much as digits as its factorization.

21743701 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 443763 (or 443756 counting only the distinct ones).

The product of its (nonzero) digits is 1176, while the sum is 25.

The square root of 21743701 is about 4663.0141539566. The cubic root of 21743701 is about 279.1115589548. Note that the first 3 decimals are identical.

The spelling of 21743701 in words is "twenty-one million, seven hundred forty-three thousand, seven hundred one".