21031002101 has 8 divisors (see below), whose sum is σ = 21840871320. Its totient is φ = 20226777088.

The previous prime is 21031002089. The next prime is 21031002149. The reversal of 21031002101 is 10120013012.

It can be written as a sum of positive squares in 4 ways, for example, as 11374009201 + 9656992900 = 106649^2 + 98270^2 .

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

It is not a de Polignac number, because 21031002101 - 2⁶ = 21031002037 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 (21031002001) 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, 1403456 + ... + 1418361.

It is an arithmetic number, because the mean of its divisors is an integer number (2730108915).

Almost surely, 2^21031002101 is an apocalyptic number.

It is an amenable number.

21031002101 is a deficient number, since it is larger than the sum of its proper divisors (809869219).

21031002101 is a wasteful number, since it uses less digits than its factorization.

21031002101 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2822103.

The product of its (nonzero) digits is 12, while the sum is 11.

Adding to 21031002101 its reverse (10120013012), we get a palindrome (31151015113).

The spelling of 21031002101 in words is "twenty-one billion, thirty-one million, two thousand, one hundred one".