1691157 has 16 divisors (see below), whose sum is σ = 2457728. Its totient is φ = 1028160.

The previous prime is 1691141. The next prime is 1691161. The reversal of 1691157 is 7511961.

It is not a de Polignac number, because 1691157 - 2⁴ = 1691141 is a prime.

1691157 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1691257) 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 15 ways as a sum of consecutive naturals, for example, 3807 + ... + 4227.

It is an arithmetic number, because the mean of its divisors is an integer number (153608).

2^1691157 is an apocalyptic number.

It is an amenable number.

1691157 is a deficient number, since it is larger than the sum of its proper divisors (766571).

1691157 is a wasteful number, since it uses less digits than its factorization.

1691157 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 540.

The product of its digits is 1890, while the sum is 30.

The square root of 1691157 is about 1300.4449238626. Note that the first 3 decimals coincide. The cubic root of 1691157 is about 119.1410187085.

It can be divided in two parts, 169 and 1157, that added together give a triangular number (1326 = T₅₁).

The spelling of 1691157 in words is "one million, six hundred ninety-one thousand, one hundred fifty-seven".