78190257780 has 144 divisors (see below), whose sum is σ = 245181081600. Its totient is φ = 20149032960.

The previous prime is 78190257763. The next prime is 78190257781. The reversal of 78190257780 is 8775209187.

It is a happy number.

It is a super-2 number, since 2×78190257780² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78190257781) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 4002276 + ... + 4021764.

It is an arithmetic number, because the mean of its divisors is an integer number (1702646400).

Almost surely, 2^78190257780 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 78190257780, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (122590540800).

78190257780 is an abundant number, since it is smaller than the sum of its proper divisors (166990823820).

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

78190257780 is a wasteful number, since it uses less digits than its factorization.

78190257780 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20254 (or 20249 counting only the distinct ones).

The product of its (nonzero) digits is 1975680, while the sum is 54.

The spelling of 78190257780 in words is "seventy-eight billion, one hundred ninety million, two hundred fifty-seven thousand, seven hundred eighty".