77444321 has 2 divisors, whose sum is σ = 77444322. Its totient is φ = 77444320.

The previous prime is 77444309. The next prime is 77444347. The reversal of 77444321 is 12344477.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 68293696 + 9150625 = 8264^2 + 3025^2 .

It is an emirp because it is prime and its reverse (12344477) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-77444321 is a prime.

It is a nialpdrome in base 10.

It is not a weakly prime, because it can be changed into another prime (77444371) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 38722160 + 38722161.

It is an arithmetic number, because the mean of its divisors is an integer number (38722161).

Almost surely, 2^77444321 is an apocalyptic number.

It is an amenable number.

77444321 is a deficient number, since it is larger than the sum of its proper divisors (1).

77444321 is an equidigital number, since it uses as much as digits as its factorization.

77444321 is an evil number, because the sum of its binary digits is even.

The product of its digits is 18816, while the sum is 32.

The square root of 77444321 is about 8800.2455079390. The cubic root of 77444321 is about 426.2488223610.

Adding to 77444321 its reverse (12344477), we get a palindrome (89788798).

The spelling of 77444321 in words is "seventy-seven million, four hundred forty-four thousand, three hundred twenty-one".