21121221001011 has 8 divisors (see below), whose sum is σ = 28478050788240. Its totient is φ = 13922602607232.

The previous prime is 21121221000961. The next prime is 21121221001033. The reversal of 21121221001011 is 11010012212112.

It is a happy number.

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

It is not a de Polignac number, because 21121221001011 - 2⁷ = 21121221000883 is a prime.

It is a super-2 number, since 2×21121221001011² (a number of 27 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (21121221001051) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 39552848050 + ... + 39552848583.

It is an arithmetic number, because the mean of its divisors is an integer number (3559756348530).

Almost surely, 2^{21121221001011} is an apocalyptic number.

21121221001011 is a deficient number, since it is larger than the sum of its proper divisors (7356829787229).

21121221001011 is an equidigital number, since it uses as much as digits as its factorization.

21121221001011 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 79105696725.

The product of its (nonzero) digits is 16, while the sum is 15.

Adding to 21121221001011 its reverse (11010012212112), we get a palindrome (32131233213123).

The spelling of 21121221001011 in words is "twenty-one trillion, one hundred twenty-one billion, two hundred twenty-one million, one thousand, eleven".