618443640 has 64 divisors (see below), whose sum is σ = 2061482400. Its totient is φ = 164918016.

The previous prime is 618443611. The next prime is 618443659. The reversal of 618443640 is 46344816.

618443640 is a `hidden beast` number, since 6 + 1 + 8 + 4 + 4 + 3 + 640 = 666.

It is a hoax number, since the sum of its digits (36) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 618443595 and 618443604.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 285237 + ... + 287396.

Almost surely, 2^618443640 is an apocalyptic number.

618443640 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

618443640 is an abundant number, since it is smaller than the sum of its proper divisors (1443038760).

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

618443640 is a wasteful number, since it uses less digits than its factorization.

618443640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 572653 (or 572643 counting only the distinct ones).

The product of its (nonzero) digits is 55296, while the sum is 36.

The square root of 618443640 is about 24868.5270975183. The cubic root of 618443640 is about 851.9877998650.

The spelling of 618443640 in words is "six hundred eighteen million, four hundred forty-three thousand, six hundred forty".