618623820 has 72 divisors (see below), whose sum is σ = 1878523920. Its totient is φ = 164787840.

The previous prime is 618623779. The next prime is 618623833. The reversal of 618623820 is 28326816.

618623820 is a `hidden beast` number, since 6 + 1 + 8 + 623 + 8 + 20 = 666.

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

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

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 306615 + ... + 308625.

It is an arithmetic number, because the mean of its divisors is an integer number (26090610).

Almost surely, 2^618623820 is an apocalyptic number.

618623820 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

618623820 is an abundant number, since it is smaller than the sum of its proper divisors (1259900100).

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

618623820 is a wasteful number, since it uses less digits than its factorization.

618623820 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3735 (or 3730 counting only the distinct ones).

The product of its (nonzero) digits is 27648, while the sum is 36.

The square root of 618623820 is about 24872.1494849159. The cubic root of 618623820 is about 852.0705324138.

The spelling of 618623820 in words is "six hundred eighteen million, six hundred twenty-three thousand, eight hundred twenty".