777778890 has 64 divisors (see below), whose sum is σ = 2159087616. Its totient is φ = 175632192.

The previous prime is 777778867. The next prime is 777778891. The reversal of 777778890 is 98877777.

It is not an unprimeable number, because it can be changed into a prime (777778891) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 4882 + ... + 39741.

It is an arithmetic number, because the mean of its divisors is an integer number (33735744).

Almost surely, 2^777778890 is an apocalyptic number.

777778890 is a gapful number since it is divisible by the number (70) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 777778890, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1079543808).

777778890 is an abundant number, since it is smaller than the sum of its proper divisors (1381308726).

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

777778890 is a wasteful number, since it uses less digits than its factorization.

777778890 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 44723.

The product of its (nonzero) digits is 9680832, while the sum is 60.

The square root of 777778890 is about 27888.6874915260. The cubic root of 777778890 is about 919.6418304892.

The spelling of 777778890 in words is "seven hundred seventy-seven million, seven hundred seventy-eight thousand, eight hundred ninety".