2001215220 has 24 divisors (see below), whose sum is σ = 5603402784. Its totient is φ = 533657376.

The previous prime is 2001215201. The next prime is 2001215221. The reversal of 2001215220 is 225121002.

It is a Harshad number since it is a multiple of its sum of digits (15).

It is a self number, because there is not a number n which added to its sum of digits gives 2001215220.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2001215221) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 16676734 + ... + 16676853.

It is an arithmetic number, because the mean of its divisors is an integer number (233475116).

Almost surely, 2^2001215220 is an apocalyptic number.

2001215220 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

2001215220 is an abundant number, since it is smaller than the sum of its proper divisors (3602187564).

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

2001215220 is a wasteful number, since it uses less digits than its factorization.

2001215220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 33353599 (or 33353597 counting only the distinct ones).

The product of its (nonzero) digits is 80, while the sum is 15.

The square root of 2001215220 is about 44734.9440594263. The cubic root of 2001215220 is about 1260.1761784387.

Adding to 2001215220 its reverse (225121002), we get a palindrome (2226336222).

The spelling of 2001215220 in words is "two billion, one million, two hundred fifteen thousand, two hundred twenty".