2156842 has 16 divisors (see below), whose sum is σ = 3434400. Its totient is φ = 1013040.

The previous prime is 2156839. The next prime is 2156849. The reversal of 2156842 is 2486512.

It is a self number, because there is not a number n which added to its sum of digits gives 2156842.

It is not an unprimeable number, because it can be changed into a prime (2156849) 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, 7884 + ... + 8152.

It is an arithmetic number, because the mean of its divisors is an integer number (214650).

2^2156842 is an apocalyptic number.

2156842 is a deficient number, since it is larger than the sum of its proper divisors (1277558).

2156842 is a wasteful number, since it uses less digits than its factorization.

2156842 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 501.

The product of its digits is 3840, while the sum is 28.

The square root of 2156842 is about 1468.6190792714. The cubic root of 2156842 is about 129.2030534093.

The spelling of 2156842 in words is "two million, one hundred fifty-six thousand, eight hundred forty-two".