78209620 has 24 divisors (see below), whose sum is σ = 165499488. Its totient is φ = 31044000.

The previous prime is 78209603. The next prime is 78209629. The reversal of 78209620 is 2690287.

It is a super-2 number, since 2×78209620² = 12233489321088800, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78209629) 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, 12306 + ... + 17545.

It is an arithmetic number, because the mean of its divisors is an integer number (6895812).

Almost surely, 2^78209620 is an apocalyptic number.

It is an amenable number.

78209620 is an abundant number, since it is smaller than the sum of its proper divisors (87289868).

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

78209620 is a wasteful number, since it uses less digits than its factorization.

78209620 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 29991 (or 29989 counting only the distinct ones).

The product of its (nonzero) digits is 12096, while the sum is 34.

The square root of 78209620 is about 8843.6202994023. The cubic root of 78209620 is about 427.6482756862.

The spelling of 78209620 in words is "seventy-eight million, two hundred nine thousand, six hundred twenty".