1001100020 has 24 divisors (see below), whose sum is σ = 2103036264. Its totient is φ = 400301696.

The previous prime is 1001100007. The next prime is 1001100049. The reversal of 1001100020 is 200011001.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 8976016 + 992124004 = 2996^2 + 31498^2 .

It is a Harshad number since it is a multiple of its sum of digits (5).

It is a junction number, because it is equal to n+sod(n) for n = 1001099977 and 1001100013.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 66734 + ... + 80346.

It is an arithmetic number, because the mean of its divisors is an integer number (87626511).

Almost surely, 2^1001100020 is an apocalyptic number.

1001100020 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1001100020 is an abundant number, since it is smaller than the sum of its proper divisors (1101936244).

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

1001100020 is a wasteful number, since it uses less digits than its factorization.

1001100020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17299 (or 17297 counting only the distinct ones).

The product of its (nonzero) digits is 2, while the sum is 5.

The square root of 1001100020 is about 31640.1646645526. The cubic root of 1001100020 is about 1000.3665389661.

Adding to 1001100020 its reverse (200011001), we get a palindrome (1201111021).

The spelling of 1001100020 in words is "one billion, one million, one hundred thousand, twenty".