2155647 has 16 divisors (see below), whose sum is σ = 3196928. Its totient is φ = 1283040.

The previous prime is 2155639. The next prime is 2155661. The reversal of 2155647 is 7465512.

It is not a de Polignac number, because 2155647 - 2³ = 2155639 is a prime.

It is a Smith number, since the sum of its digits (30) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2155627) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 318 + ... + 2100.

It is an arithmetic number, because the mean of its divisors is an integer number (199808).

2^2155647 is an apocalyptic number.

2155647 is a deficient number, since it is larger than the sum of its proper divisors (1041281).

2155647 is a wasteful number, since it uses less digits than its factorization.

2155647 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1830.

The product of its digits is 8400, while the sum is 30.

The square root of 2155647 is about 1468.2121781269. The cubic root of 2155647 is about 129.1791873167.

The spelling of 2155647 in words is "two million, one hundred fifty-five thousand, six hundred forty-seven".