78213388 has 48 divisors (see below), whose sum is σ = 155320704. Its totient is φ = 34151040.

The previous prime is 78213371. The next prime is 78213389. The reversal of 78213388 is 88331287.

It is a super-2 number, since 2×78213388² = 12234668124877088, which contains 22 as substring.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors.

It is a self number, because there is not a number n which added to its sum of digits gives 78213388.

It is not an unprimeable number, because it can be changed into a prime (78213389) 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 15 ways as a sum of consecutive naturals, for example, 126456 + ... + 127072.

It is an arithmetic number, because the mean of its divisors is an integer number (3235848).

Almost surely, 2^78213388 is an apocalyptic number.

It is an amenable number.

78213388 is a deficient number, since it is larger than the sum of its proper divisors (77107316).

78213388 is a wasteful number, since it uses less digits than its factorization.

78213388 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 742 (or 740 counting only the distinct ones).

The product of its digits is 64512, while the sum is 40.

The square root of 78213388 is about 8843.8333317629. The cubic root of 78213388 is about 427.6551433529.

The spelling of 78213388 in words is "seventy-eight million, two hundred thirteen thousand, three hundred eighty-eight".