1021440 has 160 divisors (see below), whose sum is σ = 3928320. Its totient is φ = 221184.

The previous prime is 1021429. The next prime is 1021441. The reversal of 1021440 is 441201.

1021440 = 53² + 54² + ... + 147².

It is a tau number, because it is divible by the number of its divisors (160).

It is a Harshad number since it is a multiple of its sum of digits (12).

It is a nialpdrome in base 16.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1021441) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 53751 + ... + 53769.

It is an arithmetic number, because the mean of its divisors is an integer number (24552).

2^1021440 is an apocalyptic number.

1021440 is a gapful number since it is divisible by the number (10) 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 1021440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1964160).

1021440 is an abundant number, since it is smaller than the sum of its proper divisors (2906880).

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

1021440 is an equidigital number, since it uses as much as digits as its factorization.

1021440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 52 (or 36 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 12.

The square root of 1021440 is about 1010.6631486306. The cubic root of 1021440 is about 100.7096191619.

Adding to 1021440 its reverse (441201), we get a palindrome (1462641).

The spelling of 1021440 in words is "one million, twenty-one thousand, four hundred forty".