163556820 has 120 divisors (see below), whose sum is σ = 586422144. Its totient is φ = 37381824.

The previous prime is 163556797. The next prime is 163556863. The reversal of 163556820 is 28655361.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 4129 + ... + 18551.

Almost surely, 2^163556820 is an apocalyptic number.

163556820 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 163556820, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (293211072).

163556820 is an abundant number, since it is smaller than the sum of its proper divisors (422865324).

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

163556820 is a wasteful number, since it uses less digits than its factorization.

163556820 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14451 (or 14440 counting only the distinct ones).

The product of its (nonzero) digits is 43200, while the sum is 36.

The square root of 163556820 is about 12788.9334973640. The cubic root of 163556820 is about 546.8768665841.

The spelling of 163556820 in words is "one hundred sixty-three million, five hundred fifty-six thousand, eight hundred twenty".