1000021320 has 48 divisors (see below), whose sum is σ = 3250070460. Its totient is φ = 266672256.

The previous prime is 1000021291. The next prime is 1000021333. The reversal of 1000021320 is 231200001.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 805083876 + 194937444 = 28374^2 + 13962^2 .

It is a Harshad number since it is a multiple of its sum of digits (9).

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1388559 + ... + 1389278.

Almost surely, 2^1000021320 is an apocalyptic number.

1000021320 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1000021320 is an abundant number, since it is smaller than the sum of its proper divisors (2250049140).

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

1000021320 is a wasteful number, since it uses less digits than its factorization.

1000021320 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2777854 (or 2777847 counting only the distinct ones).

The product of its (nonzero) digits is 12, while the sum is 9.

The square root of 1000021320 is about 31623.1136986856. The cubic root of 1000021320 is about 1000.0071066162.

Adding to 1000021320 its reverse (231200001), we get a palindrome (1231221321).

The spelling of 1000021320 in words is "one billion, twenty-one thousand, three hundred twenty".