78486428 has 24 divisors (see below), whose sum is σ = 142938432. Its totient is φ = 37678784.

The previous prime is 78486409. The next prime is 78486439. The reversal of 78486428 is 82468487.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (47).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 6026 + ... + 13902.

It is an arithmetic number, because the mean of its divisors is an integer number (5955768).

Almost surely, 2^78486428 is an apocalyptic number.

It is an amenable number.

78486428 is a deficient number, since it is larger than the sum of its proper divisors (64452004).

78486428 is a wasteful number, since it uses less digits than its factorization.

78486428 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7981 (or 7979 counting only the distinct ones).

The product of its digits is 688128, while the sum is 47.

The square root of 78486428 is about 8859.2566279570. The cubic root of 78486428 is about 428.1522080707.

The spelling of 78486428 in words is "seventy-eight million, four hundred eighty-six thousand, four hundred twenty-eight".