2157855 has 16 divisors (see below), whose sum is σ = 3945984. Its totient is φ = 986400.

The previous prime is 2157851. The next prime is 2157863. The reversal of 2157855 is 5587512.

It is a happy number.

It is not a de Polignac number, because 2157855 - 2² = 2157851 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2157851) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 10171 + ... + 10380.

It is an arithmetic number, because the mean of its divisors is an integer number (246624).

2^2157855 is an apocalyptic number.

2157855 is a deficient number, since it is larger than the sum of its proper divisors (1788129).

2157855 is a wasteful number, since it uses less digits than its factorization.

2157855 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20566.

The product of its digits is 14000, while the sum is 33.

The square root of 2157855 is about 1468.9639205917. The cubic root of 2157855 is about 129.2232777632.

The spelling of 2157855 in words is "two million, one hundred fifty-seven thousand, eight hundred fifty-five".