1025121440 has 192 divisors, whose sum is σ = 2961100800. Its totient is φ = 327545856.

The previous prime is 1025121413. The next prime is 1025121451. The reversal of 1025121440 is 441215201.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (20).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1425401 + ... + 1426119.

It is an arithmetic number, because the mean of its divisors is an integer number (15422400).

Almost surely, 2^1025121440 is an apocalyptic number.

1025121440 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 1025121440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1480550400).

1025121440 is an abundant number, since it is smaller than the sum of its proper divisors (1935979360).

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

1025121440 is a wasteful number, since it uses less digits than its factorization.

1025121440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 827 (or 819 counting only the distinct ones).

The product of its (nonzero) digits is 320, while the sum is 20.

The square root of 1025121440 is about 32017.5177051563. The cubic root of 1025121440 is about 1008.3046551201.

Adding to 1025121440 its reverse (441215201), we get a palindrome (1466336641).

The spelling of 1025121440 in words is "one billion, twenty-five million, one hundred twenty-one thousand, four hundred forty".