78277680 has 120 divisors (see below), whose sum is σ = 283138128. Its totient is φ = 19266048.

The previous prime is 78277649. The next prime is 78277691. The reversal of 78277680 is 8677287.

It is a tau number, because it is divible by the number of its divisors (120).

It is a super-2 number, since 2×78277680² = 12254790372364800, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (45).

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 23 ways as a sum of consecutive naturals, for example, 5179 + ... + 13541.

Almost surely, 2^78277680 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 78277680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (141569064).

78277680 is an abundant number, since it is smaller than the sum of its proper divisors (204860448).

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

78277680 is a wasteful number, since it uses less digits than its factorization.

78277680 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8395 (or 8386 counting only the distinct ones).

The product of its (nonzero) digits is 263424, while the sum is 45.

The square root of 78277680 is about 8847.4674342435. The cubic root of 78277680 is about 427.7722898542.

The spelling of 78277680 in words is "seventy-eight million, two hundred seventy-seven thousand, six hundred eighty".