1664409600 has 672 divisors, whose sum is σ = 7150851840. Its totient is φ = 371589120.

The previous prime is 1664409589. The next prime is 1664409629. The reversal of 1664409600 is 69044661.

1664409600 is a `hidden beast` number, since 1 + 6 + 6 + 4 + 40 + 9 + 600 = 666.

It is a tau number, because it is divible by the number of its divisors (672).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 38707179 + ... + 38707221.

Almost surely, 2^1664409600 is an apocalyptic number.

1664409600 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 1664409600, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3575425920).

1664409600 is an abundant number, since it is smaller than the sum of its proper divisors (5486442240).

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

1664409600 is an equidigital number, since it uses as much as digits as its factorization.

1664409600 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 95 (or 60 counting only the distinct ones).

The product of its (nonzero) digits is 31104, while the sum is 36.

The square root of 1664409600 is about 40797.1763728815. The cubic root of 1664409600 is about 1185.0956500263.

The spelling of 1664409600 in words is "one billion, six hundred sixty-four million, four hundred nine thousand, six hundred".