78171533867952 has 240 divisors, whose sum is σ = 263438871055360. Its totient is φ = 21138723560448.

The previous prime is 78171533867849. The next prime is 78171533867953. The reversal of 78171533867952 is 25976833517187.

78171533867952 is a `hidden beast` number, since 7 + 8 + 1 + 7 + 1 + 533 + 86 + 7 + 9 + 5 + 2 = 666.

It is a super-2 number, since 2×78171533867952² (a number of 29 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (72).

It is not an unprimeable number, because it can be changed into a prime (78171533867953) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 17808393 + ... + 21759639.

Almost surely, 2^{78171533867952} is an apocalyptic number.

78171533867952 is a gapful number since it is divisible by the number (72) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 78171533867952, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (131719435527680).

78171533867952 is an abundant number, since it is smaller than the sum of its proper divisors (185267337187408).

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

78171533867952 is a wasteful number, since it uses less digits than its factorization.

78171533867952 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3952320 (or 3952311 counting only the distinct ones).

The product of its digits is 533433600, while the sum is 72.

The spelling of 78171533867952 in words is "seventy-eight trillion, one hundred seventy-one billion, five hundred thirty-three million, eight hundred sixty-seven thousand, nine hundred fifty-two".