77725440 has 288 divisors, whose sum is σ = 298751040. Its totient is φ = 19021824.

The previous prime is 77725399. The next prime is 77725457. The reversal of 77725440 is 4452777.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (288).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 77725395 and 77725404.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 449194 + ... + 449366.

It is an arithmetic number, because the mean of its divisors is an integer number (1037330).

Almost surely, 2^77725440 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 77725440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (149375520).

77725440 is an abundant number, since it is smaller than the sum of its proper divisors (221025600).

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

77725440 is a wasteful number, since it uses less digits than its factorization.

77725440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 216 (or 196 counting only the distinct ones).

The product of its (nonzero) digits is 54880, while the sum is 36.

The square root of 77725440 is about 8816.2032644444. The cubic root of 77725440 is about 426.7639535098.

The spelling of 77725440 in words is "seventy-seven million, seven hundred twenty-five thousand, four hundred forty".