210021000001 has 4 divisors (see below), whose sum is σ = 210146838100. Its totient is φ = 209895161904.

The previous prime is 210020999999. The next prime is 210021000019. The reversal of 210021000001 is 100000120012.

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 106552627776 + 103468372225 = 326424^2 + 321665^2 .

It is a cyclic number.

It is not a de Polignac number, because 210021000001 - 2¹ = 210020999999 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (210021000401) 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, 62916546 + ... + 62919883.

It is an arithmetic number, because the mean of its divisors is an integer number (52536709525).

Almost surely, 2^210021000001 is an apocalyptic number.

It is an amenable number.

210021000001 is a deficient number, since it is larger than the sum of its proper divisors (125838099).

210021000001 is a wasteful number, since it uses less digits than its factorization.

210021000001 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 125838098.

The product of its (nonzero) digits is 4, while the sum is 7.

Adding to 210021000001 its reverse (100000120012), we get a palindrome (310021120013).

The spelling of 210021000001 in words is "two hundred ten billion, twenty-one million, one", and thus it is an aban number.