77073221 has 2 divisors, whose sum is σ = 77073222. Its totient is φ = 77073220.

The previous prime is 77073203. The next prime is 77073229. The reversal of 77073221 is 12237077.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 73017025 + 4056196 = 8545^2 + 2014^2 .

It is an emirp because it is prime and its reverse (12237077) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 77073221 - 2²² = 72878917 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (77073229) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 38536610 + 38536611.

It is an arithmetic number, because the mean of its divisors is an integer number (38536611).

Almost surely, 2^77073221 is an apocalyptic number.

It is an amenable number.

77073221 is a deficient number, since it is larger than the sum of its proper divisors (1).

77073221 is an equidigital number, since it uses as much as digits as its factorization.

77073221 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 4116, while the sum is 29.

The square root of 77073221 is about 8779.1355496996. The cubic root of 77073221 is about 425.5668947111.

The spelling of 77073221 in words is "seventy-seven million, seventy-three thousand, two hundred twenty-one".