101221001001 has 32 divisors (see below), whose sum is σ = 157148709120. Its totient is φ = 64269608832.

The previous prime is 101221000967. The next prime is 101221001051. The reversal of 101221001001 is 100100122101.

It is a happy number.

It is not a de Polignac number, because 101221001001 - 2²² = 101216806697 is a prime.

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 (101221001051) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 205086 + ... + 494471.

It is an arithmetic number, because the mean of its divisors is an integer number (4910897160).

Almost surely, 2^101221001001 is an apocalyptic number.

It is an amenable number.

101221001001 is a deficient number, since it is larger than the sum of its proper divisors (55927708119).

101221001001 is a wasteful number, since it uses less digits than its factorization.

101221001001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 699822 (or 699816 counting only the distinct ones).

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

Adding to 101221001001 its reverse (100100122101), we get a palindrome (201321123102).

The spelling of 101221001001 in words is "one hundred one billion, two hundred twenty-one million, one thousand, one".