2120021000 has 32 divisors (see below), whose sum is σ = 4960851480. Its totient is φ = 848008000.

The previous prime is 2120020997. The next prime is 2120021003. The reversal of 2120021000 is 1200212.

It is an interprime number because it is at equal distance from previous prime (2120020997) and next prime (2120021003).

It can be written as a sum of positive squares in 4 ways, for example, as 250842244 + 1869178756 = 15838^2 + 43234^2 .

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

It is not an unprimeable number, because it can be changed into a prime (2120021003) 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, 1059011 + ... + 1061010.

Almost surely, 2^2120021000 is an apocalyptic number.

2120021000 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

2120021000 is an abundant number, since it is smaller than the sum of its proper divisors (2840830480).

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

2120021000 is a wasteful number, since it uses less digits than its factorization.

2120021000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2120042 (or 2120028 counting only the distinct ones).

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

The square root of 2120021000 is about 46043.6857777481. The cubic root of 2120021000 is about 1284.6358994068.

Adding to 2120021000 its reverse (1200212), we get a palindrome (2121221212).

The spelling of 2120021000 in words is "two billion, one hundred twenty million, twenty-one thousand".