77433636361 has 3 divisors (see below), whose sum is σ = 77433914631. Its totient is φ = 77433358092.

The previous prime is 77433636359. The next prime is 77433636383. The reversal of 77433636361 is 16363633477.

The square root of 77433636361 is 278269.

It is a perfect power (a square), and thus also a powerful number.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 16363633477 = 431 ⋅37966667.

It can be written as a sum of positive squares in only one way, i.e., 2478147961 + 74955488400 = 49781^2 + 273780^2 .

It is not a de Polignac number, because 77433636361 - 2¹ = 77433636359 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (77433636461) by changing a digit.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 139135 + ... + 417403.

It is an arithmetic number, because the mean of its divisors is an integer number (25811304877).

Almost surely, 2^77433636361 is an apocalyptic number.

77433636361 is the 278269-th square number.

77433636361 is the 139135-th centered octagonal number.

It is an amenable number.

77433636361 is a deficient number, since it is larger than the sum of its proper divisors (278270).

77433636361 is an frugal number, since it uses more digits than its factorization.

77433636361 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 556538 (or 278269 counting only the distinct ones).

The product of its digits is 3429216, while the sum is 49.

Multiplying 77433636361 by its sum of digits (49), we get a square (3794248181689 = 1947883²).

The spelling of 77433636361 in words is "seventy-seven billion, four hundred thirty-three million, six hundred thirty-six thousand, three hundred sixty-one".