21200400241 has 4 divisors (see below), whose sum is σ = 22316210800. Its totient is φ = 20084589684.

The previous prime is 21200400211. The next prime is 21200400251. The reversal of 21200400241 is 14200400212.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 21200400241 - 2¹³ = 21200392049 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21200400211) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 557905251 + ... + 557905288.

It is an arithmetic number, because the mean of its divisors is an integer number (5579052700).

Almost surely, 2^21200400241 is an apocalyptic number.

It is an amenable number.

21200400241 is a deficient number, since it is larger than the sum of its proper divisors (1115810559).

21200400241 is a wasteful number, since it uses less digits than its factorization.

21200400241 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1115810558.

The product of its (nonzero) digits is 128, while the sum is 16.

Adding to 21200400241 its reverse (14200400212), we get a palindrome (35400800453).

The spelling of 21200400241 in words is "twenty-one billion, two hundred million, four hundred thousand, two hundred forty-one".