1025820 has 72 divisors (see below), whose sum is σ = 3210480. Its totient is φ = 264960.

The previous prime is 1025819. The next prime is 1025839. The reversal of 1025820 is 285201.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a junction number, because it is equal to n+sod(n) for n = 1025793 and 1025802.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 7311 + ... + 7449.

It is an arithmetic number, because the mean of its divisors is an integer number (44590).

2^1025820 is an apocalyptic number.

1025820 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 1025820, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1605240).

1025820 is an abundant number, since it is smaller than the sum of its proper divisors (2184660).

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

1025820 is a wasteful number, since it uses less digits than its factorization.

1025820 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 195 (or 190 counting only the distinct ones).

The product of its (nonzero) digits is 160, while the sum is 18.

The square root of 1025820 is about 1012.8277247390. The cubic root of 1025820 is about 100.8533636565.

The spelling of 1025820 in words is "one million, twenty-five thousand, eight hundred twenty".