21001012021006 has 8 divisors (see below), whose sum is σ = 31749561480960. Its totient is φ = 10417824860688.

The previous prime is 21001012021001. The next prime is 21001012021013. The reversal of 21001012021006 is 60012021010012.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21001012021001) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 41340574591 + ... + 41340575098.

It is an arithmetic number, because the mean of its divisors is an integer number (3968695185120).

Almost surely, 2^{21001012021006} is an apocalyptic number.

21001012021006 is a deficient number, since it is larger than the sum of its proper divisors (10748549459954).

21001012021006 is a wasteful number, since it uses less digits than its factorization.

21001012021006 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 82681149818.

The product of its (nonzero) digits is 48, while the sum is 16.

Adding to 21001012021006 its reverse (60012021010012), we get a palindrome (81013033031018).

The spelling of 21001012021006 in words is "twenty-one trillion, one billion, twelve million, twenty-one thousand, six".