21013100205 has 8 divisors (see below), whose sum is σ = 33620960352. Its totient is φ = 11206986768.

The previous prime is 21013100201. The next prime is 21013100209. The reversal of 21013100205 is 50200131012.

It is an interprime number because it is at equal distance from previous prime (21013100201) and next prime (21013100209).

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 21013100205 - 2² = 21013100201 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (15), and also a Moran number because the ratio is a prime number: 1400873347 = 21013100205 / (2 + 1 + 0 + 1 + 3 + 1 + 0 + 0 + 2 + 0 + 5).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21013100201) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 700436659 + ... + 700436688.

It is an arithmetic number, because the mean of its divisors is an integer number (4202620044).

Almost surely, 2^21013100205 is an apocalyptic number.

It is an amenable number.

21013100205 is a deficient number, since it is larger than the sum of its proper divisors (12607860147).

21013100205 is a wasteful number, since it uses less digits than its factorization.

21013100205 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1400873355.

The product of its (nonzero) digits is 60, while the sum is 15.

Adding to 21013100205 its reverse (50200131012), we get a palindrome (71213231217).

The spelling of 21013100205 in words is "twenty-one billion, thirteen million, one hundred thousand, two hundred five".