1025021220 has 96 divisors (see below), whose sum is σ = 3015290880. Its totient is φ = 259670400.

The previous prime is 1025021203. The next prime is 1025021227. The reversal of 1025021220 is 221205201.

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 1025021220.

It is not an unprimeable number, because it can be changed into a prime (1025021227) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 205921 + ... + 210839.

It is an arithmetic number, because the mean of its divisors is an integer number (31409280).

Almost surely, 2^1025021220 is an apocalyptic number.

1025021220 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1025021220, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1507645440).

1025021220 is an abundant number, since it is smaller than the sum of its proper divisors (1990269660).

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

1025021220 is a wasteful number, since it uses less digits than its factorization.

1025021220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5105 (or 5103 counting only the distinct ones).

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

The square root of 1025021220 is about 32015.9525861718. The cubic root of 1025021220 is about 1008.2717954081.

Adding to 1025021220 its reverse (221205201), we get a palindrome (1246226421).

The spelling of 1025021220 in words is "one billion, twenty-five million, twenty-one thousand, two hundred twenty".