21201035205 has 16 divisors (see below), whose sum is σ = 38767607424. Its totient is φ = 9691901760.

The previous prime is 21201035137. The next prime is 21201035287. The reversal of 21201035205 is 50253010212.

It is not a de Polignac number, because 21201035205 - 2⁹ = 21201034693 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 100957206 + ... + 100957415.

It is an arithmetic number, because the mean of its divisors is an integer number (2422975464).

Almost surely, 2^21201035205 is an apocalyptic number.

It is an amenable number.

21201035205 is a deficient number, since it is larger than the sum of its proper divisors (17566572219).

21201035205 is a wasteful number, since it uses less digits than its factorization.

21201035205 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 201914636.

The product of its (nonzero) digits is 600, while the sum is 21.

Adding to 21201035205 its reverse (50253010212), we get a palindrome (71454045417).

The spelling of 21201035205 in words is "twenty-one billion, two hundred one million, thirty-five thousand, two hundred five".