21200102001 has 16 divisors (see below), whose sum is σ = 33823525120. Its totient is φ = 13046216400.

The previous prime is 21200101963. The next prime is 21200102003. The reversal of 21200102001 is 10020100212.

It is not a de Polignac number, because 21200102001 - 2¹⁴ = 21200085617 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (9).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21200102003) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 30199225 + ... + 30199926.

It is an arithmetic number, because the mean of its divisors is an integer number (2113970320).

Almost surely, 2^21200102001 is an apocalyptic number.

It is an amenable number.

21200102001 is a deficient number, since it is larger than the sum of its proper divisors (12623423119).

21200102001 is a wasteful number, since it uses less digits than its factorization.

21200102001 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 60399173 (or 60399167 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 9.

Adding to 21200102001 its reverse (10020100212), we get a palindrome (31220202213).

It can be divided in two parts, 21200 and 102001, that added together give a square (123201 = 351²).

The spelling of 21200102001 in words is "twenty-one billion, two hundred million, one hundred two thousand, one".