1020921408 has 140 divisors (see below), whose sum is σ = 3259340700. Its totient is φ = 314108928.

The previous prime is 1020921373. The next prime is 1020921413. The reversal of 1020921408 is 8041290201.

It can be written as a sum of positive squares in 2 ways, for example, as 418120704 + 602800704 = 20448^2 + 24552^2 .

It is a Harshad number since it is a multiple of its sum of digits (27).

It is an unprimeable number.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 59818 + ... + 74966.

It is an arithmetic number, because the mean of its divisors is an integer number (23281005).

Almost surely, 2^1020921408 is an apocalyptic number.

1020921408 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1020921408, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1629670350).

1020921408 is an abundant number, since it is smaller than the sum of its proper divisors (2238419292).

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

1020921408 is a wasteful number, since it uses less digits than its factorization.

1020921408 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15186 (or 15167 counting only the distinct ones).

The product of its (nonzero) digits is 1152, while the sum is 27.

The square root of 1020921408 is about 31951.8607908835. The cubic root of 1020921408 is about 1006.9257262502.

The spelling of 1020921408 in words is "one billion, twenty million, nine hundred twenty-one thousand, four hundred eight".