391488077 has 2 divisors, whose sum is σ = 391488078. Its totient is φ = 391488076.

The previous prime is 391488067. The next prime is 391488109. The reversal of 391488077 is 770884193.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 326669476 + 64818601 = 18074^2 + 8051^2 .

It is a cyclic number.

It is not a de Polignac number, because 391488077 - 2¹⁴ = 391471693 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (391488017) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 195744038 + 195744039.

It is an arithmetic number, because the mean of its divisors is an integer number (195744039).

Almost surely, 2^391488077 is an apocalyptic number.

It is an amenable number.

391488077 is a deficient number, since it is larger than the sum of its proper divisors (1).

391488077 is an equidigital number, since it uses as much as digits as its factorization.

391488077 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 338688, while the sum is 47.

The square root of 391488077 is about 19786.0576416829. The cubic root of 391488077 is about 731.5424177180.

The spelling of 391488077 in words is "three hundred ninety-one million, four hundred eighty-eight thousand, seventy-seven".