618140640 has 384 divisors, whose sum is σ = 2255662080. Its totient is φ = 141115392.

The previous prime is 618140639. The next prime is 618140657. The reversal of 618140640 is 46041816.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a junction number, because it is equal to n+sod(n) for n = 618140598 and 618140607.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 8467644 + ... + 8467716.

It is an arithmetic number, because the mean of its divisors is an integer number (5874120).

Almost surely, 2^618140640 is an apocalyptic number.

618140640 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 618140640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1127831040).

618140640 is an abundant number, since it is smaller than the sum of its proper divisors (1637521440).

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

618140640 is a wasteful number, since it uses less digits than its factorization.

618140640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 186 (or 178 counting only the distinct ones).

The product of its (nonzero) digits is 4608, while the sum is 30.

The square root of 618140640 is about 24862.4343136387. The cubic root of 618140640 is about 851.8486362949.

It can be divided in two parts, 618 and 140640, that multiplied together give a triangular number (86915520 = T₁₃₁₈₄).

The spelling of 618140640 in words is "six hundred eighteen million, one hundred forty thousand, six hundred forty".