155664 has 60 divisors (see below), whose sum is σ = 464256. Its totient is φ = 48576.

The previous prime is 155663. The next prime is 155671. The reversal of 155664 is 466551.

155664 = 71² + 72² + ... + 93².

It is a happy number.

Its product of digits (3600) is a multiple of the sum of its prime divisors (75).

It is a nialpdrome in base 12.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (155663) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 3289 + ... + 3335.

2¹⁵⁵⁶⁶⁴ is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 155664, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (232128).

155664 is an abundant number, since it is smaller than the sum of its proper divisors (308592).

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

155664 is a wasteful number, since it uses less digits than its factorization.

155664 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 84 (or 75 counting only the distinct ones).

The product of its digits is 3600, while the sum is 27.

The square root of 155664 is about 394.5427733466. The cubic root of 155664 is about 53.7934496339.

The spelling of 155664 in words is "one hundred fifty-five thousand, six hundred sixty-four".