21011210002001 has 4 divisors (see below), whose sum is σ = 21091100534592. Its totient is φ = 20931319469412.

The previous prime is 21011210001979. The next prime is 21011210002021. The reversal of 21011210002001 is 10020001211012.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 21011210002001 - 2⁶ = 21011210001937 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21011210002021) 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, 39945265901 + ... + 39945266426.

It is an arithmetic number, because the mean of its divisors is an integer number (5272775133648).

Almost surely, 2^{21011210002001} is an apocalyptic number.

It is an amenable number.

21011210002001 is a deficient number, since it is larger than the sum of its proper divisors (79890532591).

21011210002001 is an equidigital number, since it uses as much as digits as its factorization.

21011210002001 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 79890532590.

The product of its (nonzero) digits is 8, while the sum is 11.

Adding to 21011210002001 its reverse (10020001211012), we get a palindrome (31031211213013).

The spelling of 21011210002001 in words is "twenty-one trillion, eleven billion, two hundred ten million, two thousand, one".