21020012101 has 8 divisors (see below), whose sum is σ = 22936576608. Its totient is φ = 19104390000.

The previous prime is 21020012099. The next prime is 21020012129. The reversal of 21020012101 is 10121002012.

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

It is a cyclic number.

It is not a de Polignac number, because 21020012101 - 2¹ = 21020012099 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21020012161) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 188550 + ... + 278551.

It is an arithmetic number, because the mean of its divisors is an integer number (2867072076).

Almost surely, 2^21020012101 is an apocalyptic number.

It is an amenable number.

21020012101 is a deficient number, since it is larger than the sum of its proper divisors (1916564507).

21020012101 is a wasteful number, since it uses less digits than its factorization.

21020012101 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 471203.

The product of its (nonzero) digits is 8, while the sum is 10.

Adding to 21020012101 its reverse (10121002012), we get a palindrome (31141014113).

The spelling of 21020012101 in words is "twenty-one billion, twenty million, twelve thousand, one hundred one".