1664557123600 has 240 divisors, whose sum is σ = 4635985777920. Its totient is φ = 562565376000.

The previous prime is 1664557123571. The next prime is 1664557123631. The reversal of 1664557123600 is 63217554661.

It is a hoax number, since the sum of its digits (46) coincides with the sum of the digits of its distinct prime factors.

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, 64748349 + ... + 64774051.

It is an arithmetic number, because the mean of its divisors is an integer number (19316607408).

Almost surely, 2^{1664557123600} is an apocalyptic number.

1664557123600 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 1664557123600, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2317992888960).

1664557123600 is an abundant number, since it is smaller than the sum of its proper divisors (2971428654320).

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

1664557123600 is a wasteful number, since it uses less digits than its factorization.

1664557123600 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 26058 (or 26047 counting only the distinct ones).

The product of its (nonzero) digits is 907200, while the sum is 46.

The spelling of 1664557123600 in words is "one trillion, six hundred sixty-four billion, five hundred fifty-seven million, one hundred twenty-three thousand, six hundred".