78396434807040 has 2592 divisors, whose sum is σ = 342547299634176. Its totient is φ = 17096072232960.

The previous prime is 78396434807029. The next prime is 78396434807051. The reversal of 78396434807040 is 4070843469387.

It is a happy number.

78396434807040 is a `hidden beast` number, since 7 + 8 + 3 + 9 + 6 + 43 + 480 + 70 + 40 = 666.

It is an interprime number because it is at equal distance from previous prime (78396434807029) and next prime (78396434807051).

It is a tau number, because it is divible by the number of its divisors (2592).

It is a super-2 number, since 2×78396434807040² (a number of 29 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (63).

It is an unprimeable number.

It is a polite number, since it can be written in 287 ways as a sum of consecutive naturals, for example, 34490291344 + ... + 34490293616.

Almost surely, 2^{78396434807040} is an apocalyptic number.

78396434807040 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 78396434807040, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (171273649817088).

78396434807040 is an abundant number, since it is smaller than the sum of its proper divisors (264150864827136).

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

78396434807040 is a wasteful number, since it uses less digits than its factorization.

78396434807040 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2427 (or 2394 counting only the distinct ones).

The product of its (nonzero) digits is 97542144, while the sum is 63.

The spelling of 78396434807040 in words is "seventy-eight trillion, three hundred ninety-six billion, four hundred thirty-four million, eight hundred seven thousand, forty".