396550391509 has 2 divisors, whose sum is σ = 396550391510. Its totient is φ = 396550391508.

The previous prime is 396550391491. The next prime is 396550391537. The reversal of 396550391509 is 905193055693.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 384427280484 + 12123111025 = 620022^2 + 110105^2 .

It is an emirp because it is prime and its reverse (905193055693) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 396550391509 - 2²⁵ = 396516837077 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 396550391509.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (396550791509) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 198275195754 + 198275195755.

It is an arithmetic number, because the mean of its divisors is an integer number (198275195755).

Almost surely, 2^396550391509 is an apocalyptic number.

It is an amenable number.

396550391509 is a deficient number, since it is larger than the sum of its proper divisors (1).

396550391509 is an equidigital number, since it uses as much as digits as its factorization.

396550391509 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 4920750, while the sum is 55.

The spelling of 396550391509 in words is "three hundred ninety-six billion, five hundred fifty million, three hundred ninety-one thousand, five hundred nine".