1001201220 has 72 divisors (see below), whose sum is σ = 3141716760. Its totient is φ = 257779200.

The previous prime is 1001201197. The next prime is 1001201231. The reversal of 1001201220 is 221021001.

It can be written as a sum of positive squares in 4 ways, for example, as 617796 + 1000583424 = 786^2 + 31632^2 .

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

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 90681 + ... + 101120.

It is an arithmetic number, because the mean of its divisors is an integer number (43634955).

Almost surely, 2^1001201220 is an apocalyptic number.

1001201220 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1001201220 is an abundant number, since it is smaller than the sum of its proper divisors (2140515540).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1001201220 is a wasteful number, since it uses less digits than its factorization.

1001201220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 191845 (or 191840 counting only the distinct ones).

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

The square root of 1001201220 is about 31641.7638572820. The cubic root of 1001201220 is about 1000.4002464481.

Adding to 1001201220 its reverse (221021001), we get a palindrome (1222222221).

The spelling of 1001201220 in words is "one billion, one million, two hundred one thousand, two hundred twenty".