1001020221 has 16 divisors (see below), whose sum is σ = 1486057600. Its totient is φ = 665967744.

The previous prime is 1001020213. The next prime is 1001020243. The reversal of 1001020221 is 1220201001.

It is not a de Polignac number, because 1001020221 - 2³ = 1001020213 is a prime.

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

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1001020271) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 24916 + ... + 51213.

It is an arithmetic number, because the mean of its divisors is an integer number (92878600).

Almost surely, 2^1001020221 is an apocalyptic number.

It is an amenable number.

1001020221 is a deficient number, since it is larger than the sum of its proper divisors (485037379).

1001020221 is an equidigital number, since it uses as much as digits as its factorization.

1001020221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 76625 (or 76619 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 9.

The square root of 1001020221 is about 31638.9035998405. The cubic root of 1001020221 is about 1000.3399580821.

Adding to 1001020221 its reverse (1220201001), we get a palindrome (2221221222).

The spelling of 1001020221 in words is "one billion, one million, twenty thousand, two hundred twenty-one".