77720496 has 160 divisors (see below), whose sum is σ = 244270080. Its totient is φ = 20815872.

The previous prime is 77720471. The next prime is 77720497. The reversal of 77720496 is 69402777.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is not an unprimeable number, because it can be changed into a prime (77720497) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 687736 + ... + 687848.

It is an arithmetic number, because the mean of its divisors is an integer number (1526688).

Almost surely, 2^77720496 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 77720496, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (122135040).

77720496 is an abundant number, since it is smaller than the sum of its proper divisors (166549584).

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

77720496 is a wasteful number, since it uses less digits than its factorization.

77720496 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 243 (or 237 counting only the distinct ones).

The product of its (nonzero) digits is 148176, while the sum is 42.

The square root of 77720496 is about 8815.9228671762. The cubic root of 77720496 is about 426.7549047105.

The spelling of 77720496 in words is "seventy-seven million, seven hundred twenty thousand, four hundred ninety-six".