1021002120 has 48 divisors (see below), whose sum is σ = 3318258060. Its totient is φ = 272267136.

The previous prime is 1021002113. The next prime is 1021002179. The reversal of 1021002120 is 212001201.

It can be written as a sum of positive squares in 2 ways, for example, as 1015441956 + 5560164 = 31866^2 + 2358^2 .

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, 1417699 + ... + 1418418.

Almost surely, 2^1021002120 is an apocalyptic number.

1021002120 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1021002120 is an abundant number, since it is smaller than the sum of its proper divisors (2297255940).

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

1021002120 is a wasteful number, since it uses less digits than its factorization.

1021002120 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2836134 (or 2836127 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 9.

The square root of 1021002120 is about 31953.1237909535. The cubic root of 1021002120 is about 1006.9522607274.

Adding to 1021002120 its reverse (212001201), we get a palindrome (1233003321).

The spelling of 1021002120 in words is "one billion, twenty-one million, two thousand, one hundred twenty".