78300557 has 4 divisors (see below), whose sum is σ = 79777980. Its totient is φ = 76823136.

The previous prime is 78300511. The next prime is 78300559. The reversal of 78300557 is 75500387.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 75500387 = 37 ⋅2040551.

It can be written as a sum of positive squares in 2 ways, for example, as 54671236 + 23629321 = 7394^2 + 4861^2 .

It is a cyclic number.

It is not a de Polignac number, because 78300557 - 2¹² = 78296461 is a prime.

It is a super-2 number, since 2×78300557² = 12261954453020498, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78300559) 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 3 ways as a sum of consecutive naturals, for example, 738632 + ... + 738737.

It is an arithmetic number, because the mean of its divisors is an integer number (19944495).

Almost surely, 2^78300557 is an apocalyptic number.

It is an amenable number.

78300557 is a deficient number, since it is larger than the sum of its proper divisors (1477423).

78300557 is a wasteful number, since it uses less digits than its factorization.

78300557 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1477422.

The product of its (nonzero) digits is 29400, while the sum is 35.

The square root of 78300557 is about 8848.7601956432. The cubic root of 78300557 is about 427.8139585797.

The spelling of 78300557 in words is "seventy-eight million, three hundred thousand, five hundred fifty-seven".