77249813 has 2 divisors, whose sum is σ = 77249814. Its totient is φ = 77249812.

The previous prime is 77249791. The next prime is 77249849. The reversal of 77249813 is 31894277.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 61105489 + 16144324 = 7817^2 + 4018^2 .

It is a cyclic number.

It is not a de Polignac number, because 77249813 - 2¹² = 77245717 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (77249713) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 38624906 + 38624907.

It is an arithmetic number, because the mean of its divisors is an integer number (38624907).

Almost surely, 2^77249813 is an apocalyptic number.

It is an amenable number.

77249813 is a deficient number, since it is larger than the sum of its proper divisors (1).

77249813 is an equidigital number, since it uses as much as digits as its factorization.

77249813 is an evil number, because the sum of its binary digits is even.

The product of its digits is 84672, while the sum is 41.

The square root of 77249813 is about 8789.1872775587. The cubic root of 77249813 is about 425.8916697954.

The spelling of 77249813 in words is "seventy-seven million, two hundred forty-nine thousand, eight hundred thirteen".