77980321 has 2 divisors, whose sum is σ = 77980322. Its totient is φ = 77980320.

The previous prime is 77980303. The next prime is 77980361. The reversal of 77980321 is 12308977.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 73616400 + 4363921 = 8580^2 + 2089^2 .

It is a cyclic number.

It is not a de Polignac number, because 77980321 - 2¹⁵ = 77947553 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (77980361) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 38990160 + 38990161.

It is an arithmetic number, because the mean of its divisors is an integer number (38990161).

Almost surely, 2^77980321 is an apocalyptic number.

It is an amenable number.

77980321 is a deficient number, since it is larger than the sum of its proper divisors (1).

77980321 is an equidigital number, since it uses as much as digits as its factorization.

77980321 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 21168, while the sum is 37.

The square root of 77980321 is about 8830.6466920606. The cubic root of 77980321 is about 427.2299328184.

The spelling of 77980321 in words is "seventy-seven million, nine hundred eighty thousand, three hundred twenty-one".