2156657 has 4 divisors (see below), whose sum is σ = 2162340. Its totient is φ = 2150976.

The previous prime is 2156647. The next prime is 2156659. The reversal of 2156657 is 7566512.

It is a happy number.

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 1577536 + 579121 = 1256^2 + 761^2 .

It is a cyclic number.

It is not a de Polignac number, because 2156657 - 2¹⁴ = 2140273 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2156659) 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, 2228 + ... + 3045.

It is an arithmetic number, because the mean of its divisors is an integer number (540585).

2^2156657 is an apocalyptic number.

It is an amenable number.

2156657 is a deficient number, since it is larger than the sum of its proper divisors (5683).

2156657 is an equidigital number, since it uses as much as digits as its factorization.

2156657 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5682.

The product of its digits is 12600, while the sum is 32.

The square root of 2156657 is about 1468.5560935831. The cubic root of 2156657 is about 129.1993592354.

The spelling of 2156657 in words is "two million, one hundred fifty-six thousand, six hundred fifty-seven".