1620168561648 has 960 divisors, whose sum is σ = 6203254966272. Its totient is φ = 397598699520.

The previous prime is 1620168561637. The next prime is 1620168561677. The reversal of 1620168561648 is 8461658610261.

It is a happy number.

1620168561648 is a `hidden beast` number, since 1 + 6 + 2 + 0 + 16 + 8 + 5 + 616 + 4 + 8 = 666.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a junction number, because it is equal to n+sod(n) for n = 1620168561594 and 1620168561603.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 191 ways as a sum of consecutive naturals, for example, 301087918 + ... + 301093298.

Almost surely, 2^{1620168561648} is an apocalyptic number.

1620168561648 is a gapful number since it is divisible by the number (18) 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 1620168561648, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3101627483136).

1620168561648 is an abundant number, since it is smaller than the sum of its proper divisors (4583086404624).

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

1620168561648 is a wasteful number, since it uses less digits than its factorization.

1620168561648 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5484 (or 5466 counting only the distinct ones).

The product of its (nonzero) digits is 3317760, while the sum is 54.

The spelling of 1620168561648 in words is "one trillion, six hundred twenty billion, one hundred sixty-eight million, five hundred sixty-one thousand, six hundred forty-eight".