21355100113 has 4 divisors (see below), whose sum is σ = 21366893808. Its totient is φ = 21343306420.

The previous prime is 21355100111. The next prime is 21355100159. The reversal of 21355100113 is 31100155312.

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 21355100113 - 2¹ = 21355100111 is a prime.

It is a super-2 number, since 2×21355100113² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21355100111) 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, 5894131 + ... + 5897752.

It is an arithmetic number, because the mean of its divisors is an integer number (5341723452).

Almost surely, 2^21355100113 is an apocalyptic number.

It is an amenable number.

21355100113 is a deficient number, since it is larger than the sum of its proper divisors (11793695).

21355100113 is a wasteful number, since it uses less digits than its factorization.

21355100113 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11793694.

The product of its (nonzero) digits is 450, while the sum is 22.

Adding to 21355100113 its reverse (31100155312), we get a palindrome (52455255425).

The spelling of 21355100113 in words is "twenty-one billion, three hundred fifty-five million, one hundred thousand, one hundred thirteen".