1720615478400 has 2880 divisors, whose sum is σ = 8435892021480. Its totient is φ = 341118812160.

The previous prime is 1720615478389. The next prime is 1720615478419. The reversal of 1720615478400 is 48745160271.

1720615478400 is a `hidden beast` number, since 1 + 7 + 2 + 0 + 61 + 547 + 8 + 40 + 0 = 666.

It can be written as a sum of positive squares in 12 ways, for example, as 44170588224 + 1676444890176 = 210168^2 + 1294776^2 .

It is a tau number, because it is divible by the number of its divisors (2880).

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 359 ways as a sum of consecutive naturals, for example, 2806876494 + ... + 2806877106.

Almost surely, 2^{1720615478400} is an apocalyptic number.

1720615478400 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 1720615478400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (4217946010740).

1720615478400 is an abundant number, since it is smaller than the sum of its proper divisors (6715276543080).

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

1720615478400 is a wasteful number, since it uses less digits than its factorization.

1720615478400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 693 (or 660 counting only the distinct ones).

The product of its (nonzero) digits is 376320, while the sum is 45.

The spelling of 1720615478400 in words is "one trillion, seven hundred twenty billion, six hundred fifteen million, four hundred seventy-eight thousand, four hundred".