78139280 has 40 divisors (see below), whose sum is σ = 189577152. Its totient is φ = 29896064.

The previous prime is 78139279. The next prime is 78139309. The reversal of 78139280 is 8293187.

It is a tau number, because it is divible by the number of its divisors (40).

It is a super-2 number, since 2×78139280² = 12211494157836800, which contains 22 as substring.

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 7 ways as a sum of consecutive naturals, for example, 19394 + ... + 23073.

Almost surely, 2^78139280 is an apocalyptic number.

It is an amenable number.

78139280 is an abundant number, since it is smaller than the sum of its proper divisors (111437872).

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

78139280 is a wasteful number, since it uses less digits than its factorization.

78139280 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 42503 (or 42497 counting only the distinct ones).

The product of its (nonzero) digits is 24192, while the sum is 38.

The square root of 78139280 is about 8839.6425267089. The cubic root of 78139280 is about 427.5200314360.

The spelling of 78139280 in words is "seventy-eight million, one hundred thirty-nine thousand, two hundred eighty".