2157771 has 16 divisors (see below), whose sum is σ = 3587328. Its totient is φ = 1120800.

The previous prime is 2157769. The next prime is 2157787. The reversal of 2157771 is 1777512.

2157771 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 2157771 - 2¹ = 2157769 is a prime.

2157771 is a lucky number.

It is not an unprimeable number, because it can be changed into a prime (2157721) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 4440 + ... + 4901.

It is an arithmetic number, because the mean of its divisors is an integer number (224208).

2^2157771 is an apocalyptic number.

2157771 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

2157771 is a deficient number, since it is larger than the sum of its proper divisors (1429557).

2157771 is a wasteful number, since it uses less digits than its factorization.

2157771 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9362.

The product of its digits is 3430, while the sum is 30.

The square root of 2157771 is about 1468.9353287330. The cubic root of 2157771 is about 129.2216009598.

The spelling of 2157771 in words is "two million, one hundred fifty-seven thousand, seven hundred seventy-one".