78213628 has 12 divisors (see below), whose sum is σ = 138085920. Its totient is φ = 38760512.

The previous prime is 78213623. The next prime is 78213631. The reversal of 78213628 is 82631287.

It is a super-2 number, since 2×78213628² = 12234743209844768, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78213623) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 86068 + ... + 86971.

It is an arithmetic number, because the mean of its divisors is an integer number (11507160).

Almost surely, 2^78213628 is an apocalyptic number.

It is an amenable number.

78213628 is a deficient number, since it is larger than the sum of its proper divisors (59872292).

78213628 is a wasteful number, since it uses less digits than its factorization.

78213628 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 173156 (or 173154 counting only the distinct ones).

The product of its digits is 32256, while the sum is 37.

The square root of 78213628 is about 8843.8469005292. The cubic root of 78213628 is about 427.6555807765.

It can be divided in two parts, 7821 and 3628, that added together give a square (11449 = 107²).

The spelling of 78213628 in words is "seventy-eight million, two hundred thirteen thousand, six hundred twenty-eight".