2155644 has 18 divisors (see below), whose sum is σ = 5449080. Its totient is φ = 718536.

The previous prime is 2155639. The next prime is 2155661. The reversal of 2155644 is 4465512.

2155644 is a `hidden beast` number, since 2 + 15 + 5 + 644 = 666.

It is a tau number, because it is divible by the number of its divisors (18).

It is a zygodrome in base 3.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 29904 + ... + 29975.

2^2155644 is an apocalyptic number.

It is an amenable number.

2155644 is an abundant number, since it is smaller than the sum of its proper divisors (3293436).

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

2155644 is a wasteful number, since it uses less digits than its factorization.

2155644 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 59889 (or 59884 counting only the distinct ones).

The product of its digits is 4800, while the sum is 27.

The square root of 2155644 is about 1468.2111564758. The cubic root of 2155644 is about 129.1791273908.

The spelling of 2155644 in words is "two million, one hundred fifty-five thousand, six hundred forty-four".