2123657 has 8 divisors (see below), whose sum is σ = 2291976. Its totient is φ = 1960192.

The previous prime is 2123617. The next prime is 2123663. The reversal of 2123657 is 7563212.

It can be written as a sum of positive squares in 4 ways, for example, as 456976 + 1666681 = 676^2 + 1291^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 2123657 - 2¹⁰ = 2122633 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2123617) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 278 + ... + 2079.

It is an arithmetic number, because the mean of its divisors is an integer number (286497).

2^2123657 is an apocalyptic number.

It is an amenable number.

2123657 is a deficient number, since it is larger than the sum of its proper divisors (168319).

2123657 is a wasteful number, since it uses less digits than its factorization.

2123657 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2427.

The product of its digits is 2520, while the sum is 26.

The square root of 2123657 is about 1457.2772557067. The cubic root of 2123657 is about 128.5369896591.

Adding to 2123657 its reverse (7563212), we get a palindrome (9686869).

The spelling of 2123657 in words is "two million, one hundred twenty-three thousand, six hundred fifty-seven".