997670777 has 2 divisors, whose sum is σ = 997670778. Its totient is φ = 997670776.

The previous prime is 997670767. The next prime is 997670801. The reversal of 997670777 is 777076799.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 935197561 + 62473216 = 30581^2 + 7904^2 .

It is an emirp because it is prime and its reverse (777076799) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 997670777 - 2⁴ = 997670761 is a prime.

It is not a weakly prime, because it can be changed into another prime (997670767) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 498835388 + 498835389.

It is an arithmetic number, because the mean of its divisors is an integer number (498835389).

Almost surely, 2^997670777 is an apocalyptic number.

It is an amenable number.

997670777 is a deficient number, since it is larger than the sum of its proper divisors (1).

997670777 is an equidigital number, since it uses as much as digits as its factorization.

997670777 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 8168202, while the sum is 59.

The square root of 997670777 is about 31585.9268820784. The cubic root of 997670777 is about 999.2229887432. Note that the first 3 decimals are identical.

The spelling of 997670777 in words is "nine hundred ninety-seven million, six hundred seventy thousand, seven hundred seventy-seven".