1616785920 has 480 divisors, whose sum is σ = 6112858752. Its totient is φ = 408748032.

The previous prime is 1616785871. The next prime is 1616785921. The reversal of 1616785920 is 295876161.

1616785920 is a `hidden beast` number, since 1 + 616 + 7 + 8 + 5 + 9 + 20 = 666.

It is a tau number, because it is divible by the number of its divisors (480).

It is a super-2 number, since 2×1616785920² = 5227993422220492800, which contains 22 as substring.

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

It is not an unprimeable number, because it can be changed into a prime (1616785921) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 14307784 + ... + 14307896.

Almost surely, 2^1616785920 is an apocalyptic number.

1616785920 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 1616785920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3056429376).

1616785920 is an abundant number, since it is smaller than the sum of its proper divisors (4496072832).

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

1616785920 is an equidigital number, since it uses as much as digits as its factorization.

1616785920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 174 (or 146 counting only the distinct ones).

The product of its (nonzero) digits is 181440, while the sum is 45.

The square root of 1616785920 is about 40209.2765416141. The cubic root of 1616785920 is about 1173.6830683797.

The spelling of 1616785920 in words is "one billion, six hundred sixteen million, seven hundred eighty-five thousand, nine hundred twenty".