21801241 has 8 divisors (see below), whose sum is σ = 27180864. Its totient is φ = 16987920.

The previous prime is 21801211. The next prime is 21801271. The reversal of 21801241 is 14210812.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (21801211) and next prime (21801271).

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 21801241 - 2¹⁹ = 21276953 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21801211) 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 in 7 ways as a sum of consecutive naturals, for example, 141490 + ... + 141643.

It is an arithmetic number, because the mean of its divisors is an integer number (3397608).

Almost surely, 2^21801241 is an apocalyptic number.

It is an amenable number.

21801241 is a deficient number, since it is larger than the sum of its proper divisors (5379623).

21801241 is a wasteful number, since it uses less digits than its factorization.

21801241 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 283151.

The product of its (nonzero) digits is 128, while the sum is 19.

The square root of 21801241 is about 4669.1799065789. The cubic root of 21801241 is about 279.3575448825.

The spelling of 21801241 in words is "twenty-one million, eight hundred one thousand, two hundred forty-one".