2157697 has 12 divisors (see below), whose sum is σ = 2346960. Its totient is φ = 1982232.

The previous prime is 2157679. The next prime is 2157709. The reversal of 2157697 is 7967512.

It is not a de Polignac number, because 2157697 - 2¹⁹ = 1633409 is a prime.

It is a Duffinian number.

2157697 is a lucky number.

It is not an unprimeable number, because it can be changed into a prime (2157667) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 15454 + ... + 15592.

It is an arithmetic number, because the mean of its divisors is an integer number (195580).

2^2157697 is an apocalyptic number.

It is an amenable number.

2157697 is a deficient number, since it is larger than the sum of its proper divisors (189263).

2157697 is a wasteful number, since it uses less digits than its factorization.

2157697 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 220 (or 201 counting only the distinct ones).

The product of its digits is 26460, while the sum is 37.

The square root of 2157697 is about 1468.9101402060. The cubic root of 2157697 is about 129.2201237397.

The spelling of 2157697 in words is "two million, one hundred fifty-seven thousand, six hundred ninety-seven".