78769949 has 2 divisors, whose sum is σ = 78769950. Its totient is φ = 78769948.

The previous prime is 78769921. The next prime is 78769967. The reversal of 78769949 is 94996787.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 72369049 + 6400900 = 8507^2 + 2530^2 .

It is an emirp because it is prime and its reverse (94996787) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 78769949 - 2⁸ = 78769693 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (78769919) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39384974 + 39384975.

It is an arithmetic number, because the mean of its divisors is an integer number (39384975).

Almost surely, 2^78769949 is an apocalyptic number.

It is an amenable number.

78769949 is a deficient number, since it is larger than the sum of its proper divisors (1).

78769949 is an equidigital number, since it uses as much as digits as its factorization.

78769949 is an evil number, because the sum of its binary digits is even.

The product of its digits is 6858432, while the sum is 59.

The square root of 78769949 is about 8875.2436022906. The cubic root of 78769949 is about 428.6671347475.

The spelling of 78769949 in words is "seventy-eight million, seven hundred sixty-nine thousand, nine hundred forty-nine".