2157801 has 4 divisors (see below), whose sum is σ = 2877072. Its totient is φ = 1438532.

The previous prime is 2157797. The next prime is 2157821. The reversal of 2157801 is 1087512.

2157801 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 2157801 - 2² = 2157797 is a prime.

It is a super-2 number, since 2×2157801² = 9312210311202, which contains 22 as substring.

It is a D-number.

It is not an unprimeable number, because it can be changed into a prime (2157821) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 359631 + ... + 359636.

It is an arithmetic number, because the mean of its divisors is an integer number (719268).

2^2157801 is an apocalyptic number.

It is an amenable number.

2157801 is a deficient number, since it is larger than the sum of its proper divisors (719271).

2157801 is an equidigital number, since it uses as much as digits as its factorization.

2157801 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 719270.

The product of its (nonzero) digits is 560, while the sum is 24.

The square root of 2157801 is about 1468.9455401750. The cubic root of 2157801 is about 129.2221998231. Note that the first 3 decimals are identical.

The spelling of 2157801 in words is "two million, one hundred fifty-seven thousand, eight hundred one".