78208428 has 12 divisors (see below), whose sum is σ = 182486360. Its totient is φ = 26069472.

The previous prime is 78208411. The next prime is 78208433. The reversal of 78208428 is 82480287.

It is a tau number, because it is divible by the number of its divisors (12).

It is a super-2 number, since 2×78208428² = 12233116420462368, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3258673 + ... + 3258696.

Almost surely, 2^78208428 is an apocalyptic number.

It is an amenable number.

78208428 is an abundant number, since it is smaller than the sum of its proper divisors (104277932).

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

78208428 is a wasteful number, since it uses less digits than its factorization.

78208428 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6517376 (or 6517374 counting only the distinct ones).

The product of its (nonzero) digits is 57344, while the sum is 39.

The square root of 78208428 is about 8843.5529059310. The cubic root of 78208428 is about 427.6461030662.

The spelling of 78208428 in words is "seventy-eight million, two hundred eight thousand, four hundred twenty-eight".