21160421063 has 4 divisors (see below), whose sum is σ = 21160910160. Its totient is φ = 21159931968.

The previous prime is 21160421059. The next prime is 21160421069. The reversal of 21160421063 is 36012406112.

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

It is a cyclic number.

It is not a de Polignac number, because 21160421063 - 2² = 21160421059 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21160421069) 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, 172595 + ... + 268532.

It is an arithmetic number, because the mean of its divisors is an integer number (5290227540).

Almost surely, 2^21160421063 is an apocalyptic number.

21160421063 is a deficient number, since it is larger than the sum of its proper divisors (489097).

21160421063 is an equidigital number, since it uses as much as digits as its factorization.

21160421063 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 489096.

The product of its (nonzero) digits is 1728, while the sum is 26.

Adding to 21160421063 its reverse (36012406112), we get a palindrome (57172827175).

The spelling of 21160421063 in words is "twenty-one billion, one hundred sixty million, four hundred twenty-one thousand, sixty-three".