77431668 has 48 divisors (see below), whose sum is σ = 193052160. Its totient is φ = 24070144.

The previous prime is 77431667. The next prime is 77431687. The reversal of 77431668 is 86613477.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (77431661) 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 15 ways as a sum of consecutive naturals, for example, 21373 + ... + 24731.

It is an arithmetic number, because the mean of its divisors is an integer number (4021920).

Almost surely, 2^77431668 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 77431668, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (96526080).

77431668 is an abundant number, since it is smaller than the sum of its proper divisors (115620492).

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

77431668 is a wasteful number, since it uses less digits than its factorization.

77431668 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3496 (or 3494 counting only the distinct ones).

The product of its digits is 169344, while the sum is 42.

The square root of 77431668 is about 8799.5265781745. The cubic root of 77431668 is about 426.2256073164.

The spelling of 77431668 in words is "seventy-seven million, four hundred thirty-one thousand, six hundred sixty-eight".