77800240 has 120 divisors (see below), whose sum is σ = 213736320. Its totient is φ = 26256384.

The previous prime is 77800223. The next prime is 77800259. The reversal of 77800240 is 4200877.

It is a Harshad number since it is a multiple of its sum of digits (28).

It is a junction number, because it is equal to n+sod(n) for n = 77800199 and 77800208.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 348769 + ... + 348991.

It is an arithmetic number, because the mean of its divisors is an integer number (1781136).

Almost surely, 2^77800240 is an apocalyptic number.

77800240 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 77800240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (106868160).

77800240 is an abundant number, since it is smaller than the sum of its proper divisors (135936080).

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

77800240 is a wasteful number, since it uses less digits than its factorization.

77800240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 339 (or 326 counting only the distinct ones).

The product of its (nonzero) digits is 3136, while the sum is 28.

The square root of 77800240 is about 8820.4444332471. Note that the first 4 decimals coincide. The cubic root of 77800240 is about 426.9008100698.

The spelling of 77800240 in words is "seventy-seven million, eight hundred thousand, two hundred forty".