77498989 has 2 divisors, whose sum is σ = 77498990. Its totient is φ = 77498988.

The previous prime is 77498987. The next prime is 77499007. The reversal of 77498989 is 98989477.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 75986089 + 1512900 = 8717^2 + 1230^2 .

It is a cyclic number.

It is not a de Polignac number, because 77498989 - 2¹ = 77498987 is a prime.

Together with 77498987, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (77498987) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 38749494 + 38749495.

It is an arithmetic number, because the mean of its divisors is an integer number (38749495).

Almost surely, 2^77498989 is an apocalyptic number.

It is an amenable number.

77498989 is a deficient number, since it is larger than the sum of its proper divisors (1).

77498989 is an equidigital number, since it uses as much as digits as its factorization.

77498989 is an evil number, because the sum of its binary digits is even.

The product of its digits is 9144576, while the sum is 61.

The square root of 77498989 is about 8803.3510097008. The cubic root of 77498989 is about 426.3490952171.

It can be divided in two parts, 77498 and 989, that added together give a palindrome (78487).

The spelling of 77498989 in words is "seventy-seven million, four hundred ninety-eight thousand, nine hundred eighty-nine".