1021012200 has 144 divisors (see below), whose sum is σ = 3692745420. Its totient is φ = 251320320.

The previous prime is 1021012171. The next prime is 1021012207. The reversal of 1021012200 is 22101201.

It can be written as a sum of positive squares in 6 ways, for example, as 430230564 + 590781636 = 20742^2 + 24306^2 .

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

It is not an unprimeable number, because it can be changed into a prime (1021012207) 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 35 ways as a sum of consecutive naturals, for example, 1584 + ... + 45216.

Almost surely, 2^1021012200 is an apocalyptic number.

1021012200 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 1021012200, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1846372710).

1021012200 is an abundant number, since it is smaller than the sum of its proper divisors (2671733220).

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

1021012200 is a wasteful number, since it uses less digits than its factorization.

1021012200 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 43668 (or 43656 counting only the distinct ones).

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

The square root of 1021012200 is about 31953.2815216215. The cubic root of 1021012200 is about 1006.9555744801.

Adding to 1021012200 its reverse (22101201), we get a palindrome (1043113401).

The spelling of 1021012200 in words is "one billion, twenty-one million, twelve thousand, two hundred".