1664258400 has 432 divisors, whose sum is σ = 6961054464. Its totient is φ = 380090880.

The previous prime is 1664258399. The next prime is 1664258411. The reversal of 1664258400 is 48524661.

1664258400 is a `hidden beast` number, since 1 + 6 + 642 + 5 + 8 + 4 + 0 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (432).

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 71 ways as a sum of consecutive naturals, for example, 1360189 + ... + 1361411.

It is an arithmetic number, because the mean of its divisors is an integer number (16113552).

Almost surely, 2^1664258400 is an apocalyptic number.

1664258400 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 1664258400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3480527232).

1664258400 is an abundant number, since it is smaller than the sum of its proper divisors (5296796064).

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

1664258400 is a wasteful number, since it uses less digits than its factorization.

1664258400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1265 (or 1240 counting only the distinct ones).

The product of its (nonzero) digits is 46080, while the sum is 36.

The square root of 1664258400 is about 40795.3232613740. The cubic root of 1664258400 is about 1185.0597630491.

The spelling of 1664258400 in words is "one billion, six hundred sixty-four million, two hundred fifty-eight thousand, four hundred".