1002001020 has 48 divisors (see below), whose sum is σ = 2818935168. Its totient is φ = 265930560.

The previous prime is 1002000997. The next prime is 1002001057. The reversal of 1002001020 is 201002001.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (6).

It is a super Niven number, because it is divisible the sum of any subset of its (nonzero) digits.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 26914 + ... + 52233.

It is an arithmetic number, because the mean of its divisors is an integer number (58727816).

Almost surely, 2^1002001020 is an apocalyptic number.

1002001020 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1002001020 is an abundant number, since it is smaller than the sum of its proper divisors (1816934148).

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

1002001020 is a wasteful number, since it uses less digits than its factorization.

1002001020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 79370 (or 79368 counting only the distinct ones).

The product of its (nonzero) digits is 4, while the sum is 6.

The square root of 1002001020 is about 31654.3996941973. The cubic root of 1002001020 is about 1000.6665622627. Note that the first 3 decimals are identical.

Adding to 1002001020 its reverse (201002001), we get a palindrome (1203003021).

The spelling of 1002001020 in words is "one billion, two million, one thousand, twenty".