10101221001 has 24 divisors (see below), whose sum is σ = 15036283080. Its totient is φ = 6529718016.

The previous prime is 10101220999. The next prime is 10101221023. The reversal of 10101221001 is 10012210101.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 3199599225 + 6901621776 = 56565^2 + 83076^2 .

It is not a de Polignac number, because 10101221001 - 2¹ = 10101220999 is a prime.

It is a super-2 number, since 2×10101221001² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (9).

It is not an unprimeable number, because it can be changed into a prime (10101221051) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 45805 + ... + 149333.

It is an arithmetic number, because the mean of its divisors is an integer number (626511795).

Almost surely, 2^10101221001 is an apocalyptic number.

It is an amenable number.

10101221001 is a deficient number, since it is larger than the sum of its proper divisors (4935062079).

10101221001 is a wasteful number, since it uses less digits than its factorization.

10101221001 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 103865 (or 103862 counting only the distinct ones).

The product of its (nonzero) digits is 4, while the sum is 9.

Adding to 10101221001 its reverse (10012210101), we get a palindrome (20113431102).

The spelling of 10101221001 in words is "ten billion, one hundred one million, two hundred twenty-one thousand, one".