1001311020 has 288 divisors, whose sum is σ = 3381094080. Its totient is φ = 238878720.

The previous prime is 1001311013. The next prime is 1001311021. The reversal of 1001311020 is 201131001.

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 = 1001310993 and 1001311011.

It is not an unprimeable number, because it can be changed into a prime (1001311021) by changing a digit.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 5188044 + ... + 5188236.

It is an arithmetic number, because the mean of its divisors is an integer number (11739910).

Almost surely, 2^1001311020 is an apocalyptic number.

1001311020 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 1001311020, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1690547040).

1001311020 is an abundant number, since it is smaller than the sum of its proper divisors (2379783060).

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

1001311020 is a wasteful number, since it uses less digits than its factorization.

1001311020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 305 (or 300 counting only the distinct ones).

The product of its (nonzero) digits is 6, while the sum is 9.

The square root of 1001311020 is about 31643.4988583753. The cubic root of 1001311020 is about 1000.4368158308.

Adding to 1001311020 its reverse (201131001), we get a palindrome (1202442021).

The spelling of 1001311020 in words is "one billion, one million, three hundred eleven thousand, twenty".