21002120211010 has 8 divisors (see below), whose sum is σ = 37803816379836. Its totient is φ = 8400848084400.

The previous prime is 21002120211001. The next prime is 21002120211013. The reversal of 21002120211010 is 1011202120012.

It can be written as a sum of positive squares in 2 ways, for example, as 17714342563281 + 3287777647729 = 4208841^2 + 1813223^2 .

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

It is not an unprimeable number, because it can be changed into a prime (21002120211013) 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, 1050106010541 + ... + 1050106010560.

Almost surely, 2^{21002120211010} is an apocalyptic number.

21002120211010 is a deficient number, since it is larger than the sum of its proper divisors (16801696168826).

21002120211010 is a wasteful number, since it uses less digits than its factorization.

21002120211010 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2100212021108.

The product of its (nonzero) digits is 16, while the sum is 13.

Adding to 21002120211010 its reverse (1011202120012), we get a palindrome (22013322331022).

The spelling of 21002120211010 in words is "twenty-one trillion, two billion, one hundred twenty million, two hundred eleven thousand, ten".