1663920 has 60 divisors (see below), whose sum is σ = 5590416. Its totient is φ = 443520.

The previous prime is 1663919. The next prime is 1663951. The reversal of 1663920 is 293661.

It is a happy number.

1663920 is a `hidden beast` number, since 1 + 6 + 639 + 20 = 666.

It is a tau number, because it is divible by the number of its divisors (60).

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 436 + ... + 1875.

2^1663920 is an apocalyptic number.

1663920 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 1663920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2795208).

1663920 is an abundant number, since it is smaller than the sum of its proper divisors (3926496).

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

1663920 is a wasteful number, since it uses less digits than its factorization.

1663920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2330 (or 2321 counting only the distinct ones).

The product of its (nonzero) digits is 1944, while the sum is 27.

The square root of 1663920 is about 1289.9302306714. The cubic root of 1663920 is about 118.4979436699.

It can be divided in two parts, 16 and 63920, that added together give a palindrome (63936).

The spelling of 1663920 in words is "one million, six hundred sixty-three thousand, nine hundred twenty".