21260143361 has 4 divisors (see below), whose sum is σ = 21340980672. Its totient is φ = 21179306052.

The previous prime is 21260143343. The next prime is 21260143417. The reversal of 21260143361 is 16334106212.

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 21260143361 - 2¹⁴ = 21260126977 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (21260143661) 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, 40418261 + ... + 40418786.

It is an arithmetic number, because the mean of its divisors is an integer number (5335245168).

Almost surely, 2^21260143361 is an apocalyptic number.

It is an amenable number.

21260143361 is a deficient number, since it is larger than the sum of its proper divisors (80837311).

21260143361 is an equidigital number, since it uses as much as digits as its factorization.

21260143361 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 80837310.

The product of its (nonzero) digits is 5184, while the sum is 29.

Adding to 21260143361 its reverse (16334106212), we get a palindrome (37594249573).

The spelling of 21260143361 in words is "twenty-one billion, two hundred sixty million, one hundred forty-three thousand, three hundred sixty-one".