21000320101 has 4 divisors (see below), whose sum is σ = 21724469100. Its totient is φ = 20276171104.

The previous prime is 21000320093. The next prime is 21000320137. The reversal of 21000320101 is 10102300012.

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 7695851076 + 13304469025 = 87726^2 + 115345^2 .

It is a cyclic number.

It is not a de Polignac number, because 21000320101 - 2³ = 21000320093 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 (21000320161) 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, 362074456 + ... + 362074513.

It is an arithmetic number, because the mean of its divisors is an integer number (5431117275).

Almost surely, 2^21000320101 is an apocalyptic number.

It is an amenable number.

21000320101 is a deficient number, since it is larger than the sum of its proper divisors (724148999).

21000320101 is an equidigital number, since it uses as much as digits as its factorization.

21000320101 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 724148998.

The product of its (nonzero) digits is 12, while the sum is 10.

Adding to 21000320101 its reverse (10102300012), we get a palindrome (31102620113).

The spelling of 21000320101 in words is "twenty-one billion, three hundred twenty thousand, one hundred one".