21740401 has 8 divisors (see below), whose sum is σ = 22585320. Its totient is φ = 20901888.

The previous prime is 21740387. The next prime is 21740417. The reversal of 21740401 is 10404712.

It can be written as a sum of positive squares in 4 ways, for example, as 17430625 + 4309776 = 4175^2 + 2076^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21740401 - 2²¹ = 19643249 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21740491) 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, 5995 + ... + 8911.

It is an arithmetic number, because the mean of its divisors is an integer number (2823165).

Almost surely, 2^21740401 is an apocalyptic number.

It is an amenable number.

21740401 is a deficient number, since it is larger than the sum of its proper divisors (844919).

21740401 is a wasteful number, since it uses less digits than its factorization.

21740401 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3203.

The product of its (nonzero) digits is 224, while the sum is 19.

The square root of 21740401 is about 4662.6602921508. The cubic root of 21740401 is about 279.0974381643.

The spelling of 21740401 in words is "twenty-one million, seven hundred forty thousand, four hundred one".