78395775 has 12 divisors (see below), whose sum is σ = 129614472. Its totient is φ = 41811040.

The previous prime is 78395773. The next prime is 78395791. The reversal of 78395775 is 57759387.

It is not a de Polignac number, because 78395775 - 2¹ = 78395773 is a prime.

It is a super-2 number, since 2×78395775² = 12291795075701250, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78395773) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 522564 + ... + 522713.

It is an arithmetic number, because the mean of its divisors is an integer number (10801206).

Almost surely, 2^78395775 is an apocalyptic number.

78395775 is a gapful number since it is divisible by the number (75) formed by its first and last digit.

78395775 is a deficient number, since it is larger than the sum of its proper divisors (51218697).

78395775 is a wasteful number, since it uses less digits than its factorization.

78395775 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1045290 (or 1045285 counting only the distinct ones).

The product of its digits is 1852200, while the sum is 51.

The square root of 78395775 is about 8854.1388627014. The cubic root of 78395775 is about 427.9873038275.

The spelling of 78395775 in words is "seventy-eight million, three hundred ninety-five thousand, seven hundred seventy-five".