2157745 has 16 divisors (see below), whose sum is σ = 2799360. Its totient is φ = 1591744.

The previous prime is 2157739. The next prime is 2157763. The reversal of 2157745 is 5477512.

It is a cyclic number.

It is not a de Polignac number, because 2157745 - 2³ = 2157737 is a prime.

It is an Ulam number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3012 + ... + 3658.

It is an arithmetic number, because the mean of its divisors is an integer number (174960).

2^2157745 is an apocalyptic number.

It is an amenable number.

2157745 is a deficient number, since it is larger than the sum of its proper divisors (641615).

2157745 is a wasteful number, since it uses less digits than its factorization.

2157745 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 704.

The product of its digits is 9800, while the sum is 31.

The square root of 2157745 is about 1468.9264787592. The cubic root of 2157745 is about 129.2210819404.

The spelling of 2157745 in words is "two million, one hundred fifty-seven thousand, seven hundred forty-five".