1025899920 has 120 divisors (see below), whose sum is σ = 3487026816. Its totient is φ = 270261504.

The previous prime is 1025899877. The next prime is 1025899937. The reversal of 1025899920 is 299985201.

It is a tau number, because it is divible by the number of its divisors (120).

It is a Harshad number since it is a multiple of its sum of digits (45).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 51177 + ... + 68343.

Almost surely, 2^1025899920 is an apocalyptic number.

1025899920 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 1025899920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1743513408).

1025899920 is an abundant number, since it is smaller than the sum of its proper divisors (2461126896).

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

1025899920 is a wasteful number, since it uses less digits than its factorization.

1025899920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17269 (or 17260 counting only the distinct ones).

The product of its (nonzero) digits is 116640, while the sum is 45.

The square root of 1025899920 is about 32029.6724928620. The cubic root of 1025899920 is about 1008.5598269676.

The spelling of 1025899920 in words is "one billion, twenty-five million, eight hundred ninety-nine thousand, nine hundred twenty".