155565020 has 96 divisors (see below), whose sum is σ = 367156608. Its totient is φ = 54991872.

The previous prime is 155565001. The next prime is 155565043. The reversal of 155565020 is 20565551.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 990782 + ... + 990938.

It is an arithmetic number, because the mean of its divisors is an integer number (3824548).

Almost surely, 2^155565020 is an apocalyptic number.

155565020 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 155565020, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (183578304).

155565020 is an abundant number, since it is smaller than the sum of its proper divisors (211591588).

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

155565020 is a wasteful number, since it uses less digits than its factorization.

155565020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 319 (or 317 counting only the distinct ones).

The product of its (nonzero) digits is 7500, while the sum is 29.

The square root of 155565020 is about 12472.5707053518. The cubic root of 155565020 is about 537.8204557435.

The spelling of 155565020 in words is "one hundred fifty-five million, five hundred sixty-five thousand, twenty".