1201201020 has 144 divisors (see below), whose sum is σ = 3823921920. Its totient is φ = 304819200.

The previous prime is 1201201009. The next prime is 1201201021. The reversal of 1201201020 is 201021021.

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

It is a junction number, because it is equal to n+sod(n) for n = 1201200993 and 1201201011.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1201201021) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 338616 + ... + 342144.

Almost surely, 2^1201201020 is an apocalyptic number.

1201201020 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 1201201020, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1911960960).

1201201020 is an abundant number, since it is smaller than the sum of its proper divisors (2622720900).

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

1201201020 is a wasteful number, since it uses less digits than its factorization.

1201201020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3636 (or 3631 counting only the distinct ones).

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

The square root of 1201201020 is about 34658.3470465630. The cubic root of 1201201020 is about 1063.0129715840.

Adding to 1201201020 its reverse (201021021), we get a palindrome (1402222041).

The spelling of 1201201020 in words is "one billion, two hundred one million, two hundred one thousand, twenty".