1001253440 has 56 divisors (see below), whose sum is σ = 2600992512. Its totient is φ = 364090880.

The previous prime is 1001253439. The next prime is 1001253443. The reversal of 1001253440 is 443521001.

It is a super-2 number, since 2×1001253440² = 2005016902223667200, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (20).

It is not an unprimeable number, because it can be changed into a prime (1001253443) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 138704 + ... + 145743.

Almost surely, 2^1001253440 is an apocalyptic number.

1001253440 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1001253440 is an abundant number, since it is smaller than the sum of its proper divisors (1599739072).

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

1001253440 is a wasteful number, since it uses less digits than its factorization.

1001253440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 284475 (or 284465 counting only the distinct ones).

The product of its (nonzero) digits is 480, while the sum is 20.

The square root of 1001253440 is about 31642.5890217599. The cubic root of 1001253440 is about 1000.4176388868.

Adding to 1001253440 its reverse (443521001), we get a palindrome (1444774441).

The spelling of 1001253440 in words is "one billion, one million, two hundred fifty-three thousand, four hundred forty".