1000021240 has 32 divisors (see below), whose sum is σ = 2251529280. Its totient is φ = 399745152.

The previous prime is 1000021229. The next prime is 1000021247. The reversal of 1000021240 is 421200001.

It is a super-2 number, since 2×1000021240² = 2000084960902275200, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (10).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1000021247) 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, 60337 + ... + 75103.

It is an arithmetic number, because the mean of its divisors is an integer number (70360290).

Almost surely, 2^1000021240 is an apocalyptic number.

1000021240 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1000021240 is an abundant number, since it is smaller than the sum of its proper divisors (1251508040).

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

1000021240 is a wasteful number, since it uses less digits than its factorization.

1000021240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16471 (or 16467 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 10.

The square root of 1000021240 is about 31623.1124337880. The cubic root of 1000021240 is about 1000.0070799499.

Adding to 1000021240 its reverse (421200001), we get a palindrome (1421221241).

The spelling of 1000021240 in words is "one billion, twenty-one thousand, two hundred forty".