77555897 has 2 divisors, whose sum is σ = 77555898. Its totient is φ = 77555896.

The previous prime is 77555851. The next prime is 77555903. The reversal of 77555897 is 79855577.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 52113961 + 25441936 = 7219^2 + 5044^2 .

It is a cyclic number.

It is not a de Polignac number, because 77555897 - 2²⁴ = 60778681 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (77555197) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 38777948 + 38777949.

It is an arithmetic number, because the mean of its divisors is an integer number (38777949).

Almost surely, 2^77555897 is an apocalyptic number.

It is an amenable number.

77555897 is a deficient number, since it is larger than the sum of its proper divisors (1).

77555897 is an equidigital number, since it uses as much as digits as its factorization.

77555897 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 3087000, while the sum is 53.

The square root of 77555897 is about 8806.5825948548. The cubic root of 77555897 is about 426.4534266339.

The spelling of 77555897 in words is "seventy-seven million, five hundred fifty-five thousand, eight hundred ninety-seven".