77538997 has 2 divisors, whose sum is σ = 77538998. Its totient is φ = 77538996.

The previous prime is 77538977. The next prime is 77539001. The reversal of 77538997 is 79983577.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 68574961 + 8964036 = 8281^2 + 2994^2 .

It is an emirp because it is prime and its reverse (79983577) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 77538997 - 2¹⁵ = 77506229 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (77538977) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 38769498 + 38769499.

It is an arithmetic number, because the mean of its divisors is an integer number (38769499).

Almost surely, 2^77538997 is an apocalyptic number.

It is an amenable number.

77538997 is a deficient number, since it is larger than the sum of its proper divisors (1).

77538997 is an equidigital number, since it uses as much as digits as its factorization.

77538997 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 3333960, while the sum is 55.

The square root of 77538997 is about 8805.6230330397. The cubic root of 77538997 is about 426.4224486050.

The spelling of 77538997 in words is "seventy-seven million, five hundred thirty-eight thousand, nine hundred ninety-seven".