1020020040 has 320 divisors, whose sum is σ = 3762102960. Its totient is φ = 246343680.

The previous prime is 1020019969. The next prime is 1020020041. The reversal of 1020020040 is 400200201.

It can be written as a sum of positive squares in 8 ways, for example, as 91355364 + 928664676 = 9558^2 + 30474^2 .

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 (1020020041) 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 79 ways as a sum of consecutive naturals, for example, 2569122 + ... + 2569518.

Almost surely, 2^1020020040 is an apocalyptic number.

1020020040 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 1020020040, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1881051480).

1020020040 is an abundant number, since it is smaller than the sum of its proper divisors (2742082920).

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

1020020040 is a wasteful number, since it uses less digits than its factorization.

1020020040 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 494 (or 481 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 9.

The square root of 1020020040 is about 31937.7525821715. The cubic root of 1020020040 is about 1006.6293019088.

Adding to 1020020040 its reverse (400200201), we get a palindrome (1420220241).

The spelling of 1020020040 in words is "one billion, twenty million, twenty thousand, forty".