77378280 has 128 divisors (see below), whose sum is σ = 267079680. Its totient is φ = 17568000.

The previous prime is 77378261. The next prime is 77378297. The reversal of 77378280 is 8287377.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 210657 + ... + 211023.

It is an arithmetic number, because the mean of its divisors is an integer number (2086560).

Almost surely, 2^77378280 is an apocalyptic number.

77378280 is a gapful number since it is divisible by the number (70) 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 77378280, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (133539840).

77378280 is an abundant number, since it is smaller than the sum of its proper divisors (189701400).

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

77378280 is a wasteful number, since it uses less digits than its factorization.

77378280 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 639 (or 635 counting only the distinct ones).

The product of its (nonzero) digits is 131712, while the sum is 42.

The square root of 77378280 is about 8796.4924828024. The cubic root of 77378280 is about 426.1276260246.

The spelling of 77378280 in words is "seventy-seven million, three hundred seventy-eight thousand, two hundred eighty".