1021001000 has 32 divisors (see below), whose sum is σ = 2389144680. Its totient is φ = 408400000.

The previous prime is 1021000963. The next prime is 1021001029. The reversal of 1021001000 is 1001201.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 515380804 + 505620196 = 22702^2 + 22486^2 .

It is a Harshad number since it is a multiple of its sum of digits (5).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 509501 + ... + 511500.

Almost surely, 2^1021001000 is an apocalyptic number.

1021001000 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1021001000 is an abundant number, since it is smaller than the sum of its proper divisors (1368143680).

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

1021001000 is a wasteful number, since it uses less digits than its factorization.

1021001000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1021022 (or 1021008 counting only the distinct ones).

The product of its (nonzero) digits is 2, while the sum is 5.

The square root of 1021001000 is about 31953.1062652757. The cubic root of 1021001000 is about 1006.9518925313.

Adding to 1021001000 its reverse (1001201), we get a palindrome (1022002201).

The spelling of 1021001000 in words is "one billion, twenty-one million, one thousand".