1660401 has 6 divisors (see below), whose sum is σ = 2398370. Its totient is φ = 1106928.

The previous prime is 1660387. The next prime is 1660409. The reversal of 1660401 is 1040661.

1660401 is a `hidden beast` number, since 1 + 660 + 4 + 0 + 1 = 666.

It can be written as a sum of positive squares in only one way, i.e., 893025 + 767376 = 945^2 + 876^2 .

It is not a de Polignac number, because 1660401 - 2¹¹ = 1658353 is a prime.

It is a Duffinian number.

It is a Curzon number.

1660401 is a lucky number.

It is not an unprimeable number, because it can be changed into a prime (1660409) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 92236 + ... + 92253.

2^1660401 is an apocalyptic number.

It is an amenable number.

1660401 is a deficient number, since it is larger than the sum of its proper divisors (737969).

1660401 is a wasteful number, since it uses less digits than its factorization.

1660401 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 184495 (or 184492 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 18.

The square root of 1660401 is about 1288.5654814560. The cubic root of 1660401 is about 118.4143481896.

The spelling of 1660401 in words is "one million, six hundred sixty thousand, four hundred one".