78288140 has 24 divisors (see below), whose sum is σ = 187891872. Its totient is φ = 26841600.

The previous prime is 78288121. The next prime is 78288143. The reversal of 78288140 is 4188287.

It is a happy number.

It is a super-2 number, since 2×78288140² = 12258065729319200, which contains 22 as substring.

It is a Smith number, since the sum of its digits (38) coincides with the sum of the digits of its prime factors.

It is a junction number, because it is equal to n+sod(n) for n = 78288094 and 78288103.

It is not an unprimeable number, because it can be changed into a prime (78288143) by changing a digit.

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, 279461 + ... + 279740.

It is an arithmetic number, because the mean of its divisors is an integer number (7828828).

Almost surely, 2^78288140 is an apocalyptic number.

78288140 is a gapful number since it is divisible by the number (70) formed by its first and last digit.

It is an amenable number.

78288140 is an abundant number, since it is smaller than the sum of its proper divisors (109603732).

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

78288140 is a wasteful number, since it uses less digits than its factorization.

78288140 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 559217 (or 559215 counting only the distinct ones).

The product of its (nonzero) digits is 28672, while the sum is 38.

The square root of 78288140 is about 8848.0585441101. The cubic root of 78288140 is about 427.7913429604.

The spelling of 78288140 in words is "seventy-eight million, two hundred eighty-eight thousand, one hundred forty".