78394181670 has 128 divisors (see below), whose sum is σ = 246622740480. Its totient is φ = 17340635520.

The previous prime is 78394181641. The next prime is 78394181683. The reversal of 78394181670 is 7618149387.

78394181670 is a `hidden beast` number, since 7 + 8 + 394 + 181 + 6 + 70 = 666.

It is a super-2 number, since 2×78394181670² (a number of 23 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 610417 + ... + 727596.

It is an arithmetic number, because the mean of its divisors is an integer number (1926740160).

Almost surely, 2^78394181670 is an apocalyptic number.

78394181670 is a gapful number since it is divisible by the number (70) formed by its first and last digit.

78394181670 is an abundant number, since it is smaller than the sum of its proper divisors (168228558810).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

78394181670 is a wasteful number, since it uses less digits than its factorization.

78394181670 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1338067 (or 1338061 counting only the distinct ones).

The product of its (nonzero) digits is 2032128, while the sum is 54.

The spelling of 78394181670 in words is "seventy-eight billion, three hundred ninety-four million, one hundred eighty-one thousand, six hundred seventy".