77910206440 has 256 divisors, whose sum is σ = 212482621440. Its totient is φ = 25360896000.

The previous prime is 77910206411. The next prime is 77910206441. The reversal of 77910206440 is 4460201977.

It is a Harshad number since it is a multiple of its sum of digits (40).

It is a junction number, because it is equal to n+sod(n) for n = 77910206393 and 77910206402.

It is not an unprimeable number, because it can be changed into a prime (77910206441) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 32858455 + ... + 32860825.

It is an arithmetic number, because the mean of its divisors is an integer number (830010240).

Almost surely, 2^77910206440 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 77910206440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (106241310720).

77910206440 is an abundant number, since it is smaller than the sum of its proper divisors (134572415000).

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

77910206440 is a wasteful number, since it uses less digits than its factorization.

77910206440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2624 (or 2620 counting only the distinct ones).

The product of its (nonzero) digits is 84672, while the sum is 40.

The spelling of 77910206440 in words is "seventy-seven billion, nine hundred ten million, two hundred six thousand, four hundred forty".