78298457 has 4 divisors (see below), whose sum is σ = 78824100. Its totient is φ = 77772816.

The previous prime is 78298453. The next prime is 78298471. The reversal of 78298457 is 75489287.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 75489287 = 37 ⋅2040251.

It can be written as a sum of positive squares in 2 ways, for example, as 2886601 + 75411856 = 1699^2 + 8684^2 .

It is a cyclic number.

It is not a de Polignac number, because 78298457 - 2² = 78298453 is a prime.

It is a super-2 number, since 2×78298457² = 12261296737161698, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (78298453) 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, 262598 + ... + 262895.

It is an arithmetic number, because the mean of its divisors is an integer number (19706025).

Almost surely, 2^78298457 is an apocalyptic number.

It is an amenable number.

78298457 is a deficient number, since it is larger than the sum of its proper divisors (525643).

78298457 is a wasteful number, since it uses less digits than its factorization.

78298457 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 525642.

The product of its digits is 1128960, while the sum is 50.

The square root of 78298457 is about 8848.6415341565. The cubic root of 78298457 is about 427.8101339268.

The spelling of 78298457 in words is "seventy-eight million, two hundred ninety-eight thousand, four hundred fifty-seven".