77621688 has 96 divisors (see below), whose sum is σ = 231004800. Its totient is φ = 23436864.

The previous prime is 77621659. The next prime is 77621689. The reversal of 77621688 is 88612677.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (77621689) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 30231 + ... + 32697.

It is an arithmetic number, because the mean of its divisors is an integer number (2406300).

Almost surely, 2^77621688 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 77621688, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (115502400).

77621688 is an abundant number, since it is smaller than the sum of its proper divisors (153383112).

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

77621688 is a wasteful number, since it uses less digits than its factorization.

77621688 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2521 (or 2514 counting only the distinct ones).

The product of its digits is 225792, while the sum is 45.

The square root of 77621688 is about 8810.3171339061. The cubic root of 77621688 is about 426.5739799752.

The spelling of 77621688 in words is "seventy-seven million, six hundred twenty-one thousand, six hundred eighty-eight".