391357777441 has 2 divisors, whose sum is σ = 391357777442. Its totient is φ = 391357777440.

The previous prime is 391357777381. The next prime is 391357777457. The reversal of 391357777441 is 144777753193.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 369299290000 + 22058487441 = 607700^2 + 148521^2 .

It is a cyclic number.

It is not a de Polignac number, because 391357777441 - 2¹⁷ = 391357646369 is a prime.

It is not a weakly prime, because it can be changed into another prime (391357777241) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 195678888720 + 195678888721.

It is an arithmetic number, because the mean of its divisors is an integer number (195678888721).

Almost surely, 2^391357777441 is an apocalyptic number.

It is an amenable number.

391357777441 is a deficient number, since it is larger than the sum of its proper divisors (1).

391357777441 is an equidigital number, since it uses as much as digits as its factorization.

391357777441 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 15558480, while the sum is 58.

The spelling of 391357777441 in words is "three hundred ninety-one billion, three hundred fifty-seven million, seven hundred seventy-seven thousand, four hundred forty-one".