78405312 has 28 divisors (see below), whose sum is σ = 207447896. Its totient is φ = 26135040.

The previous prime is 78405311. The next prime is 78405319. The reversal of 78405312 is 21350487.

It is a super-2 number, since 2×78405312² = 12294785899634688, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 78405312.

It is not an unprimeable number, because it can be changed into a prime (78405311) 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, 203989 + ... + 204372.

Almost surely, 2^78405312 is an apocalyptic number.

It is an amenable number.

78405312 is an abundant number, since it is smaller than the sum of its proper divisors (129042584).

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

78405312 is a wasteful number, since it uses less digits than its factorization.

78405312 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 408376 (or 408366 counting only the distinct ones).

The product of its (nonzero) digits is 6720, while the sum is 30.

The square root of 78405312 is about 8854.6774080144. The cubic root of 78405312 is about 428.0046582892.

Adding to 78405312 its reverse (21350487), we get a palindrome (99755799).

The spelling of 78405312 in words is "seventy-eight million, four hundred five thousand, three hundred twelve".