1663929 has 8 divisors (see below), whose sum is σ = 2465120. Its totient is φ = 1109268.

The previous prime is 1663919. The next prime is 1663951. The reversal of 1663929 is 9293661.

1663929 is a `hidden beast` number, since 16 + 639 + 2 + 9 = 666.

It is not a de Polignac number, because 1663929 - 2⁴ = 1663913 is a prime.

It is a Duffinian number.

It is a Curzon number.

1663929 is a lucky number.

It is a junction number, because it is equal to n+sod(n) for n = 1663893 and 1663902.

It is not an unprimeable number, because it can be changed into a prime (1663919) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 30787 + ... + 30840.

It is an arithmetic number, because the mean of its divisors is an integer number (308140).

2^1663929 is an apocalyptic number.

It is an amenable number.

1663929 is a deficient number, since it is larger than the sum of its proper divisors (801191).

1663929 is an equidigital number, since it uses as much as digits as its factorization.

1663929 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 61636 (or 61630 counting only the distinct ones).

The product of its digits is 17496, while the sum is 36.

The square root of 1663929 is about 1289.9337192275. The cubic root of 1663929 is about 118.4981573179.

It can be divided in two parts, 166 and 3929, that added together give a triangular number (4095 = T₉₀).

The spelling of 1663929 in words is "one million, six hundred sixty-three thousand, nine hundred twenty-nine".