1966501382400 has 243 divisors, whose sum is σ = 7031889742969. Its totient is φ = 524310620160.

The previous prime is 1966501382381. The next prime is 1966501382411. The reversal of 1966501382400 is 42831056691.

The square root of 1966501382400 is 1402320.

It is a perfect power (a square), and thus also a powerful number.

1966501382400 is a `hidden beast` number, since 1 + 9 + 66 + 50 + 138 + 2 + 400 = 666.

It can be written as a sum of positive squares in only one way, i.e., 707940497664 + 1258560884736 = 841392^2 + 1121856^2 .

It is a super-2 number, since 2×1966501382400² (a number of 25 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a Duffinian number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 336553879 + ... + 336559721.

Almost surely, 2^{1966501382400} is an apocalyptic number.

1966501382400 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

1966501382400 is the 1402320-th square number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1966501382400

1966501382400 is an abundant number, since it is smaller than the sum of its proper divisors (5065388360569).

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

1966501382400 is an frugal number, since it uses more digits than its factorization.

1966501382400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11718 (or 5853 counting only the distinct ones).

The product of its (nonzero) digits is 311040, while the sum is 45.

The spelling of 1966501382400 in words is "one trillion, nine hundred sixty-six billion, five hundred one million, three hundred eighty-two thousand, four hundred".