7778910478 has 4 divisors (see below), whose sum is σ = 11668365720. Its totient is φ = 3889455238.

The previous prime is 7778910463. The next prime is 7778910493. The reversal of 7778910478 is 8740198777.

It is a semiprime because it is the product of two primes.

It is an interprime number because it is at equal distance from previous prime (7778910463) and next prime (7778910493).

It is a super-2 number, since 2×7778910478² (a number of 21 digits) contains 22 as substring.

It is a Smith number, since the sum of its digits (58) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1944727618 + ... + 1944727621.

It is an arithmetic number, because the mean of its divisors is an integer number (2917091430).

Almost surely, 2^7778910478 is an apocalyptic number.

7778910478 is a deficient number, since it is larger than the sum of its proper divisors (3889455242).

7778910478 is a wasteful number, since it uses less digits than its factorization.

7778910478 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3889455241.

The product of its (nonzero) digits is 5531904, while the sum is 58.

The square root of 7778910478 is about 88198.1319416687. The cubic root of 7778910478 is about 1981.4034940864.

The spelling of 7778910478 in words is "seven billion, seven hundred seventy-eight million, nine hundred ten thousand, four hundred seventy-eight".