21012122021001 has 16 divisors (see below), whose sum is σ = 28048193098944. Its totient is φ = 13992069579264.

The previous prime is 21012122020999. The next prime is 21012122021003. The reversal of 21012122021001 is 10012022121012.

It is an interprime number because it is at equal distance from previous prime (21012122020999) and next prime (21012122021003).

It is not a de Polignac number, because 21012122021001 - 2¹ = 21012122020999 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21012122021003) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 24321885 + ... + 25170981.

It is an arithmetic number, because the mean of its divisors is an integer number (1753012068684).

Almost surely, 2^{21012122021001} is an apocalyptic number.

It is an amenable number.

21012122021001 is a deficient number, since it is larger than the sum of its proper divisors (7036071077943).

21012122021001 is an equidigital number, since it uses as much as digits as its factorization.

21012122021001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 858520.

The product of its (nonzero) digits is 32, while the sum is 15.

Adding to 21012122021001 its reverse (10012022121012), we get a palindrome (31024144142013).

The spelling of 21012122021001 in words is "twenty-one trillion, twelve billion, one hundred twenty-two million, twenty-one thousand, one".