77012320 has 288 divisors, whose sum is σ = 248209920. Its totient is φ = 22256640.

The previous prime is 77012311. The next prime is 77012333. The reversal of 77012320 is 2321077.

It is a Harshad number since it is a multiple of its sum of digits (22).

It is a junction number, because it is equal to n+sod(n) for n = 77012291 and 77012300.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 1638537 + ... + 1638583.

It is an arithmetic number, because the mean of its divisors is an integer number (861840).

Almost surely, 2^77012320 is an apocalyptic number.

77012320 is a gapful number since it is divisible by the number (70) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 77012320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (124104960).

77012320 is an abundant number, since it is smaller than the sum of its proper divisors (171197600).

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

77012320 is a wasteful number, since it uses less digits than its factorization.

77012320 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 106 (or 91 counting only the distinct ones).

The product of its (nonzero) digits is 588, while the sum is 22.

The square root of 77012320 is about 8775.6663564655. Note that the first 3 decimals coincide. The cubic root of 77012320 is about 425.4547750128.

Adding to 77012320 its reverse (2321077), we get a palindrome (79333397).

It can be divided in two parts, 770 and 12320, that multiplied together give a square (9486400 = 3080²).

The spelling of 77012320 in words is "seventy-seven million, twelve thousand, three hundred twenty".