77484989 has 2 divisors, whose sum is σ = 77484990. Its totient is φ = 77484988.

The previous prime is 77484977. The next prime is 77484991. The reversal of 77484989 is 98948477.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 74736025 + 2748964 = 8645^2 + 1658^2 .

It is a cyclic number.

It is not a de Polignac number, because 77484989 - 2⁴ = 77484973 is a prime.

Together with 77484991, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (77484949) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 38742494 + 38742495.

It is an arithmetic number, because the mean of its divisors is an integer number (38742495).

Almost surely, 2^77484989 is an apocalyptic number.

It is an amenable number.

77484989 is a deficient number, since it is larger than the sum of its proper divisors (1).

77484989 is an equidigital number, since it uses as much as digits as its factorization.

77484989 is an evil number, because the sum of its binary digits is even.

The product of its digits is 4064256, while the sum is 56.

The square root of 77484989 is about 8802.5558220326. Note that the first 3 decimals coincide. The cubic root of 77484989 is about 426.3234207024.

The spelling of 77484989 in words is "seventy-seven million, four hundred eighty-four thousand, nine hundred eighty-nine".