2111657 has 4 divisors (see below), whose sum is σ = 2131140. Its totient is φ = 2092176.

The previous prime is 2111633. The next prime is 2111677. The reversal of 2111657 is 7561112.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 1038361 + 1073296 = 1019^2 + 1036^2 .

It is a cyclic number.

It is not a de Polignac number, because 2111657 - 2¹⁸ = 1849513 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2111677) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 9578 + ... + 9795.

It is an arithmetic number, because the mean of its divisors is an integer number (532785).

2^2111657 is an apocalyptic number.

It is an amenable number.

2111657 is a deficient number, since it is larger than the sum of its proper divisors (19483).

2111657 is a wasteful number, since it uses less digits than its factorization.

2111657 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19482.

The product of its digits is 420, while the sum is 23.

The square root of 2111657 is about 1453.1541556215. The cubic root of 2111657 is about 128.2944272160.

Adding to 2111657 its reverse (7561112), we get a palindrome (9672769).

The spelling of 2111657 in words is "two million, one hundred eleven thousand, six hundred fifty-seven".