618687720 has 336 divisors, whose sum is σ = 2433477060. Its totient is φ = 141087744.

The previous prime is 618687701. The next prime is 618687733. The reversal of 618687720 is 27786816.

618687720 is a `hidden beast` number, since 618 + 6 + 8 + 7 + 7 + 20 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 567106596 + 51581124 = 23814^2 + 7182^2 .

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

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 83 ways as a sum of consecutive naturals, for example, 1428624 + ... + 1429056.

Almost surely, 2^618687720 is an apocalyptic number.

618687720 is a gapful number since it is divisible by the number (60) 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 618687720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1216738530).

618687720 is an abundant number, since it is smaller than the sum of its proper divisors (1814789340).

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

618687720 is a wasteful number, since it uses less digits than its factorization.

618687720 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 476 (or 450 counting only the distinct ones).

The product of its (nonzero) digits is 225792, while the sum is 45.

The square root of 618687720 is about 24873.4340210595. The cubic root of 618687720 is about 852.0998692691.

The spelling of 618687720 in words is "six hundred eighteen million, six hundred eighty-seven thousand, seven hundred twenty".