1028397440 has 64 divisors (see below), whose sum is σ = 2809740960. Its totient is φ = 352591872.

The previous prime is 1028397427. The next prime is 1028397443. The reversal of 1028397440 is 447938201.

It is a tau number, because it is divible by the number of its divisors (64).

It is a junction number, because it is equal to n+sod(n) for n = 1028397394 and 1028397403.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1028397443) 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, 110297 + ... + 119256.

Almost surely, 2^1028397440 is an apocalyptic number.

1028397440 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1028397440 is an abundant number, since it is smaller than the sum of its proper divisors (1781343520).

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

1028397440 is an equidigital number, since it uses as much as digits as its factorization.

1028397440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 229579 (or 229567 counting only the distinct ones).

The product of its (nonzero) digits is 48384, while the sum is 38.

The square root of 1028397440 is about 32068.6363913404. The cubic root of 1028397440 is about 1009.3775990821.

The spelling of 1028397440 in words is "one billion, twenty-eight million, three hundred ninety-seven thousand, four hundred forty".