21010012001 has 16 divisors (see below), whose sum is σ = 23387443200. Its totient is φ = 18714181200.

The previous prime is 21010011989. The next prime is 21010012019. The reversal of 21010012001 is 10021001012.

It is a de Polignac number, because none of the positive numbers 2^k-21010012001 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21010012001.

It is not an unprimeable number, because it can be changed into a prime (21010012201) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 21560 + ... + 206118.

It is an arithmetic number, because the mean of its divisors is an integer number (1461715200).

Almost surely, 2^21010012001 is an apocalyptic number.

It is an amenable number.

21010012001 is a deficient number, since it is larger than the sum of its proper divisors (2377431199).

21010012001 is a wasteful number, since it uses less digits than its factorization.

21010012001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 184780.

The product of its (nonzero) digits is 4, while the sum is 8.

Adding to 21010012001 its reverse (10021001012), we get a palindrome (31031013013).

The spelling of 21010012001 in words is "twenty-one billion, ten million, twelve thousand, one".