391990729279 has 2 divisors, whose sum is σ = 391990729280. Its totient is φ = 391990729278.

The previous prime is 391990729267. The next prime is 391990729289. The reversal of 391990729279 is 972927099193.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 391990729279 - 2³⁵ = 357630990911 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (391990729219) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 195995364639 + 195995364640.

It is an arithmetic number, because the mean of its divisors is an integer number (195995364640).

Almost surely, 2^391990729279 is an apocalyptic number.

391990729279 is a deficient number, since it is larger than the sum of its proper divisors (1).

391990729279 is an equidigital number, since it uses as much as digits as its factorization.

391990729279 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 34720812, while the sum is 67.

The spelling of 391990729279 in words is "three hundred ninety-one billion, nine hundred ninety million, seven hundred twenty-nine thousand, two hundred seventy-nine".