21021000032101 has 4 divisors (see below), whose sum is σ = 22257529445772. Its totient is φ = 19784470618432.

The previous prime is 21021000032093. The next prime is 21021000032107. The reversal of 21021000032101 is 10123000012012.

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

It can be written as a sum of positive squares in 2 ways, for example, as 12528584101476 + 8492415930625 = 3539574^2 + 2914175^2 .

It is a cyclic number.

It is not a de Polignac number, because 21021000032101 - 2³ = 21021000032093 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 (21021000032107) 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, 618264706810 + ... + 618264706843.

It is an arithmetic number, because the mean of its divisors is an integer number (5564382361443).

Almost surely, 2^{21021000032101} is an apocalyptic number.

It is an amenable number.

21021000032101 is a deficient number, since it is larger than the sum of its proper divisors (1236529413671).

21021000032101 is a wasteful number, since it uses less digits than its factorization.

21021000032101 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1236529413670.

The product of its (nonzero) digits is 24, while the sum is 13.

Adding to 21021000032101 its reverse (10123000012012), we get a palindrome (31144000044113).

The spelling of 21021000032101 in words is "twenty-one trillion, twenty-one billion, thirty-two thousand, one hundred one".