78949771 has 2 divisors, whose sum is σ = 78949772. Its totient is φ = 78949770.

The previous prime is 78949757. The next prime is 78949813. The reversal of 78949771 is 17794987.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 78949771 - 2¹³ = 78941579 is a prime.

It is not a weakly prime, because it can be changed into another prime (78949711) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39474885 + 39474886.

It is an arithmetic number, because the mean of its divisors is an integer number (39474886).

Almost surely, 2^78949771 is an apocalyptic number.

78949771 is a deficient number, since it is larger than the sum of its proper divisors (1).

78949771 is an equidigital number, since it uses as much as digits as its factorization.

78949771 is an evil number, because the sum of its binary digits is even.

The product of its digits is 889056, while the sum is 52.

The square root of 78949771 is about 8885.3683660274. The cubic root of 78949771 is about 428.9930847627.

The spelling of 78949771 in words is "seventy-eight million, nine hundred forty-nine thousand, seven hundred seventy-one".