78289540 has 24 divisors (see below), whose sum is σ = 187895232. Its totient is φ = 26842080.

The previous prime is 78289489. The next prime is 78289571. The reversal of 78289540 is 4598287.

It is a super-2 number, since 2×78289540² = 12258504146823200, 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, 279466 + ... + 279745.

It is an arithmetic number, because the mean of its divisors is an integer number (7828968).

Almost surely, 2^78289540 is an apocalyptic number.

78289540 is a gapful number since it is divisible by the number (70) formed by its first and last digit.

It is an amenable number.

78289540 is an abundant number, since it is smaller than the sum of its proper divisors (109605692).

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

78289540 is a wasteful number, since it uses less digits than its factorization.

78289540 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 559227 (or 559225 counting only the distinct ones).

The product of its (nonzero) digits is 161280, while the sum is 43.

The square root of 78289540 is about 8848.1376571570. The cubic root of 78289540 is about 427.7938929606.

The spelling of 78289540 in words is "seventy-eight million, two hundred eighty-nine thousand, five hundred forty".