1555920 has 60 divisors (see below), whose sum is σ = 5227716. Its totient is φ = 414720.

The previous prime is 1555919. The next prime is 1555943. The reversal of 1555920 is 295551.

It can be written as a sum of positive squares in 2 ways, for example, as 767376 + 788544 = 876^2 + 888^2 .

It is a tau number, because it is divible by the number of its divisors (60).

It is an Ulam number.

It is a congruent number.

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 11 ways as a sum of consecutive naturals, for example, 361 + ... + 1800.

2^1555920 is an apocalyptic number.

1555920 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 1555920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2613858).

1555920 is an abundant number, since it is smaller than the sum of its proper divisors (3671796).

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

1555920 is a wasteful number, since it uses less digits than its factorization.

1555920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2180 (or 2171 counting only the distinct ones).

The product of its (nonzero) digits is 2250, while the sum is 27.

The square root of 1555920 is about 1247.3652231804. The cubic root of 1555920 is about 115.8766028273.

The spelling of 1555920 in words is "one million, five hundred fifty-five thousand, nine hundred twenty".