1001002040 has 16 divisors (see below), whose sum is σ = 2252254680. Its totient is φ = 400400800.

The previous prime is 1001002001. The next prime is 1001002049. The reversal of 1001002040 is 402001001.

It is a Harshad number since it is a multiple of its sum of digits (8).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1001002049) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 12512486 + ... + 12512565.

Almost surely, 2^1001002040 is an apocalyptic number.

1001002040 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1001002040 is an abundant number, since it is smaller than the sum of its proper divisors (1251252640).

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

1001002040 is a wasteful number, since it uses less digits than its factorization.

1001002040 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 25025062 (or 25025058 counting only the distinct ones).

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

The square root of 1001002040 is about 31638.6162782129. The cubic root of 1001002040 is about 1000.3339018305. Note that the first 3 decimals are identical.

Adding to 1001002040 its reverse (402001001), we get a palindrome (1403003041).

The spelling of 1001002040 in words is "one billion, one million, two thousand, forty".