21012002220001 has 16 divisors (see below), whose sum is σ = 22762734243984. Its totient is φ = 19280807149824.

The previous prime is 21012002219951. The next prime is 21012002220089. The reversal of 21012002220001 is 10002220021012.

It is a happy number.

It can be written as a sum of positive squares in 8 ways, for example, as 4008708734976 + 17003293485025 = 2002176^2 + 4123505^2 .

It is a cyclic number.

It is not a de Polignac number, because 21012002220001 - 2⁹ = 21012002219489 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (13).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21012002220901) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5435446 + ... + 8459791.

It is an arithmetic number, because the mean of its divisors is an integer number (1422670890249).

Almost surely, 2^{21012002220001} is an apocalyptic number.

It is an amenable number.

21012002220001 is a deficient number, since it is larger than the sum of its proper divisors (1750732023983).

21012002220001 is a wasteful number, since it uses less digits than its factorization.

21012002220001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13895940.

The product of its (nonzero) digits is 32, while the sum is 13.

Adding to 21012002220001 its reverse (10002220021012), we get a palindrome (31014222241013).

The spelling of 21012002220001 in words is "twenty-one trillion, twelve billion, two million, two hundred twenty thousand, one".