1002121220 has 12 divisors (see below), whose sum is σ = 2104454604.
Its totient is φ = 400848480.
The previous prime is 1002121217. The next prime is 1002121243. The reversal of 1002121220 is 221212001.
It is a happy number.
It can be written as a sum of positive squares in 2 ways, for example, as 111218116 + 890903104 = 10546^2 + 29848^2
It is an unprimeable number.
It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 25053011 + ... + 25053050.
It is an arithmetic number, because the mean of its divisors is an integer number (175371217).
Almost surely, 21002121220 is an apocalyptic number.
1002121220 is a gapful number since it is divisible by the number (10) formed by its first and last digit.
It is an amenable number.
1002121220 is an abundant number, since it is smaller than the sum of its proper divisors (1102333384).
It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.
1002121220 is a wasteful number, since it uses less digits than its factorization.
1002121220 is an evil number, because the sum of its binary digits is even.
The sum of its prime factors is 50106070 (or 50106068 counting only the distinct ones).
The product of its (nonzero) digits is 16, while the sum is 11.
The square root of 1002121220 is about 31656.2982674854.
The cubic root of 1002121220 is about 1000.7065739690.
Adding to 1002121220 its reverse (221212001), we get a palindrome (1223333221).
The spelling of 1002121220 in words is "one billion, two million, one hundred twenty-one thousand, two hundred twenty".