1601640 has 64 divisors (see below), whose sum is σ = 5342400. Its totient is φ = 426816.

The previous prime is 1601629. The next prime is 1601647. The reversal of 1601640 is 461061.

1601640 is a `hidden beast` number, since 1 + 601 + 64 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is not an unprimeable number, because it can be changed into a prime (1601647) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 339 + ... + 1821.

It is an arithmetic number, because the mean of its divisors is an integer number (83475).

2^1601640 is an apocalyptic number.

1601640 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1601640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2671200).

1601640 is an abundant number, since it is smaller than the sum of its proper divisors (3740760).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1601640 is a wasteful number, since it uses less digits than its factorization.

1601640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1503 (or 1493 counting only the distinct ones).

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

The square root of 1601640 is about 1265.5591649544. The cubic root of 1601640 is about 117.0006574585. Note that the first 3 decimals are identical.

The spelling of 1601640 in words is "one million, six hundred one thousand, six hundred forty".