21241656001 has 4 divisors (see below), whose sum is σ = 21243538372. Its totient is φ = 21239773632.

The previous prime is 21241655999. The next prime is 21241656019. The reversal of 21241656001 is 10065614212.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 6328361601 + 14913294400 = 79551^2 + 122120^2 .

It is a cyclic number.

It is not a de Polignac number, because 21241656001 - 2¹ = 21241655999 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21241656031) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 924156 + ... + 946861.

It is an arithmetic number, because the mean of its divisors is an integer number (5310884593).

Almost surely, 2^21241656001 is an apocalyptic number.

It is an amenable number.

21241656001 is a deficient number, since it is larger than the sum of its proper divisors (1882371).

21241656001 is a wasteful number, since it uses less digits than its factorization.

21241656001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1882370.

The product of its (nonzero) digits is 2880, while the sum is 28.

The spelling of 21241656001 in words is "twenty-one billion, two hundred forty-one million, six hundred fifty-six thousand, one".