1918161 has 40 divisors (see below), whose sum is σ = 3484800. Its totient is φ = 1026432.

The previous prime is 1918157. The next prime is 1918181. The reversal of 1918161 is 1618191.

1918161 is nontrivially palindromic in base 16.

It is not a de Polignac number, because 1918161 - 2² = 1918157 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

1918161 is a strobogrammatic number because it is the same when read upside-down.

It is not an unprimeable number, because it can be changed into a prime (1918121) by changing a digit.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 9540 + ... + 9738.

It is an arithmetic number, because the mean of its divisors is an integer number (87120).

2^1918161 is an apocalyptic number.

It is an amenable number.

1918161 is a deficient number, since it is larger than the sum of its proper divisors (1566639).

1918161 is a wasteful number, since it uses less digits than its factorization.

1918161 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 235 (or 226 counting only the distinct ones).

The product of its digits is 432, while the sum is 27.

The square root of 1918161 is about 1384.9768951141. The cubic root of 1918161 is about 124.2496056137.

The spelling of 1918161 in words is "one million, nine hundred eighteen thousand, one hundred sixty-one".