77641913 has 2 divisors, whose sum is σ = 77641914. Its totient is φ = 77641912.

The previous prime is 77641897. The next prime is 77641931. The reversal of 77641913 is 31914677.

Together with next prime (77641931) it forms an Ormiston pair, because they use the same digits, order apart.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 69422224 + 8219689 = 8332^2 + 2867^2 .

It is a cyclic number.

It is not a de Polignac number, because 77641913 - 2⁴ = 77641897 is a prime.

It is not a weakly prime, because it can be changed into another prime (77641933) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 38820956 + 38820957.

It is an arithmetic number, because the mean of its divisors is an integer number (38820957).

Almost surely, 2^77641913 is an apocalyptic number.

It is an amenable number.

77641913 is a deficient number, since it is larger than the sum of its proper divisors (1).

77641913 is an equidigital number, since it uses as much as digits as its factorization.

77641913 is an evil number, because the sum of its binary digits is even.

The product of its digits is 31752, while the sum is 38.

The square root of 77641913 is about 8811.4648611908. The cubic root of 77641913 is about 426.6110259339.

The spelling of 77641913 in words is "seventy-seven million, six hundred forty-one thousand, nine hundred thirteen".