77778480 has 160 divisors (see below), whose sum is σ = 263358144. Its totient is φ = 18874368.

The previous prime is 77778469. The next prime is 77778509. The reversal of 77778480 is 8487777.

It is a super-2 number, since 2×77778480² = 12098983902220800, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (48).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 302512 + ... + 302768.

Almost surely, 2^77778480 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 77778480, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (131679072).

77778480 is an abundant number, since it is smaller than the sum of its proper divisors (185579664).

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

77778480 is a wasteful number, since it uses less digits than its factorization.

77778480 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 383 (or 377 counting only the distinct ones).

The product of its (nonzero) digits is 614656, while the sum is 48.

The square root of 77778480 is about 8819.2108490499. The cubic root of 77778480 is about 426.8610063031.

The spelling of 77778480 in words is "seventy-seven million, seven hundred seventy-eight thousand, four hundred eighty".