21221001211001 has 8 divisors (see below), whose sum is σ = 22343443123680. Its totient is φ = 20099114009568.

The previous prime is 21221001210979. The next prime is 21221001211099. The reversal of 21221001211001 is 10011210012212.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21221001211001 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21221001811001) 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, 138599276 + ... + 138752301.

It is an arithmetic number, because the mean of its divisors is an integer number (2792930390460).

Almost surely, 2^{21221001211001} is an apocalyptic number.

It is an amenable number.

21221001211001 is a deficient number, since it is larger than the sum of its proper divisors (1122441912679).

21221001211001 is a wasteful number, since it uses less digits than its factorization.

21221001211001 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 277355623.

The product of its (nonzero) digits is 16, while the sum is 14.

Adding to 21221001211001 its reverse (10011210012212), we get a palindrome (31232211223213).

The spelling of 21221001211001 in words is "twenty-one trillion, two hundred twenty-one billion, one million, two hundred eleven thousand, one".