78297428 has 24 divisors (see below), whose sum is σ = 155977920. Its totient is φ = 34041920.

The previous prime is 78297421. The next prime is 78297431. The reversal of 78297428 is 82479287.

It is a happy number.

It is a super-2 number, since 2×78297428² = 12260974462830368, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78297421) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 37673 + ... + 39696.

It is an arithmetic number, because the mean of its divisors is an integer number (6499080).

Almost surely, 2^78297428 is an apocalyptic number.

It is an amenable number.

78297428 is a deficient number, since it is larger than the sum of its proper divisors (77680492).

78297428 is a wasteful number, since it uses less digits than its factorization.

78297428 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 77407 (or 77405 counting only the distinct ones).

The product of its digits is 451584, while the sum is 47.

The square root of 78297428 is about 8848.5833894471. The cubic root of 78297428 is about 427.8082598220.

The spelling of 78297428 in words is "seventy-eight million, two hundred ninety-seven thousand, four hundred twenty-eight".