78028397 has 4 divisors (see below), whose sum is σ = 81420960. Its totient is φ = 74635836.

The previous prime is 78028393. The next prime is 78028403. The reversal of 78028397 is 79382087.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 78028397 - 2² = 78028393 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78028393) 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, 1696247 + ... + 1696292.

It is an arithmetic number, because the mean of its divisors is an integer number (20355240).

Almost surely, 2^78028397 is an apocalyptic number.

It is an amenable number.

78028397 is a deficient number, since it is larger than the sum of its proper divisors (3392563).

78028397 is a wasteful number, since it uses less digits than its factorization.

78028397 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3392562.

The product of its (nonzero) digits is 169344, while the sum is 44.

The square root of 78028397 is about 8833.3683835783. The cubic root of 78028397 is about 427.3177126004.

The spelling of 78028397 in words is "seventy-eight million, twenty-eight thousand, three hundred ninety-seven".