78158545920 has 1760 divisors, whose sum is σ = 366180460800. Its totient is φ = 15479341056.

The previous prime is 78158545909. The next prime is 78158545931. The reversal of 78158545920 is 2954585187.

78158545920 is a `hidden beast` number, since 7 + 8 + 1 + 5 + 8 + 545 + 92 + 0 = 666.

It is an interprime number because it is at equal distance from previous prime (78158545909) and next prime (78158545931).

It is a super-2 number, since 2×78158545920² (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 an unprimeable number.

It is a polite number, since it can be written in 159 ways as a sum of consecutive naturals, for example, 717050826 + ... + 717050934.

It is an arithmetic number, because the mean of its divisors is an integer number (208057080).

Almost surely, 2^78158545920 is an apocalyptic number.

78158545920 is a gapful number since it is divisible by the number (70) 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 78158545920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (183090230400).

78158545920 is an abundant number, since it is smaller than the sum of its proper divisors (288021914880).

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

78158545920 is a wasteful number, since it uses less digits than its factorization.

78158545920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 185 (or 158 counting only the distinct ones).

The product of its (nonzero) digits is 4032000, while the sum is 54.

The spelling of 78158545920 in words is "seventy-eight billion, one hundred fifty-eight million, five hundred forty-five thousand, nine hundred twenty".