778171620 has 48 divisors (see below), whose sum is σ = 2181009600. Its totient is φ = 207309696.

The previous prime is 778171519. The next prime is 778171633. The reversal of 778171620 is 26171877.

It is a Smith number, since the sum of its digits (39) coincides with the sum of the digits of its prime factors.

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, 61606 + ... + 73154.

It is an arithmetic number, because the mean of its divisors is an integer number (45437700).

Almost surely, 2^778171620 is an apocalyptic number.

It is an amenable number.

778171620 is an abundant number, since it is smaller than the sum of its proper divisors (1402837980).

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

778171620 is a wasteful number, since it uses less digits than its factorization.

778171620 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12684 (or 12682 counting only the distinct ones).

The product of its (nonzero) digits is 32928, while the sum is 39.

The square root of 778171620 is about 27895.7276298719. The cubic root of 778171620 is about 919.7965917666.

It can be divided in two parts, 7781 and 71620, that added together give a triangular number (79401 = T₃₉₈).

The spelling of 778171620 in words is "seven hundred seventy-eight million, one hundred seventy-one thousand, six hundred twenty".