77721356 has 12 divisors (see below), whose sum is σ = 136150560. Its totient is φ = 38821200.

The previous prime is 77721313. The next prime is 77721359. The reversal of 77721356 is 65312777.

It is not an unprimeable number, because it can be changed into a prime (77721359) 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 3 ways as a sum of consecutive naturals, for example, 5195 + ... + 13506.

It is an arithmetic number, because the mean of its divisors is an integer number (11345880).

Almost surely, 2^77721356 is an apocalyptic number.

It is an amenable number.

77721356 is a deficient number, since it is larger than the sum of its proper divisors (58429204).

77721356 is a wasteful number, since it uses less digits than its factorization.

77721356 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19744 (or 19742 counting only the distinct ones).

The product of its digits is 61740, while the sum is 38.

The square root of 77721356 is about 8815.9716424226. The cubic root of 77721356 is about 426.7564787606.

The spelling of 77721356 in words is "seventy-seven million, seven hundred twenty-one thousand, three hundred fifty-six".