617668920 has 192 divisors, whose sum is σ = 2226687840. Its totient is φ = 147225600.

The previous prime is 617668903. The next prime is 617668927. The reversal of 617668920 is 29866716.

617668920 is a `hidden beast` number, since 617 + 6 + 6 + 8 + 9 + 20 = 666.

It is a Smith number, since the sum of its digits (45) 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 (45).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (617668927) 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, 240282 + ... + 242838.

Almost surely, 2^617668920 is an apocalyptic number.

617668920 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 617668920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1113343920).

617668920 is an abundant number, since it is smaller than the sum of its proper divisors (1609018920).

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

617668920 is a wasteful number, since it uses less digits than its factorization.

617668920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2646 (or 2639 counting only the distinct ones).

The product of its (nonzero) digits is 217728, while the sum is 45.

The square root of 617668920 is about 24852.9459018443. The cubic root of 617668920 is about 851.6318914999.

The spelling of 617668920 in words is "six hundred seventeen million, six hundred sixty-eight thousand, nine hundred twenty".