2155724 has 6 divisors (see below), whose sum is σ = 3772524. Its totient is φ = 1077860.

The previous prime is 2155723. The next prime is 2155733. The reversal of 2155724 is 4275512.

It is a junction number, because it is equal to n+sod(n) for n = 2155693 and 2155702.

It is not an unprimeable number, because it can be changed into a prime (2155723) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 269462 + ... + 269469.

It is an arithmetic number, because the mean of its divisors is an integer number (628754).

2^2155724 is an apocalyptic number.

It is an amenable number.

2155724 is a deficient number, since it is larger than the sum of its proper divisors (1616800).

2155724 is a wasteful number, since it uses less digits than its factorization.

2155724 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 538935 (or 538933 counting only the distinct ones).

The product of its digits is 2800, while the sum is 26.

The square root of 2155724 is about 1468.2384002607. The cubic root of 2155724 is about 129.1807253977.

The spelling of 2155724 in words is "two million, one hundred fifty-five thousand, seven hundred twenty-four".