7861393549 has 2 divisors, whose sum is σ = 7861393550. Its totient is φ = 7861393548.

The previous prime is 7861393541. The next prime is 7861393609. The reversal of 7861393549 is 9453931687.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 7721136900 + 140256649 = 87870^2 + 11843^2 .

It is a cyclic number.

It is not a de Polignac number, because 7861393549 - 2³ = 7861393541 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 7861393549.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (7861393541) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3930696774 + 3930696775.

It is an arithmetic number, because the mean of its divisors is an integer number (3930696775).

Almost surely, 2^7861393549 is an apocalyptic number.

It is an amenable number.

7861393549 is a deficient number, since it is larger than the sum of its proper divisors (1).

7861393549 is an equidigital number, since it uses as much as digits as its factorization.

7861393549 is an evil number, because the sum of its binary digits is even.

The product of its digits is 4898880, while the sum is 55.

The square root of 7861393549 is about 88664.4999365586. The cubic root of 7861393549 is about 1988.3821053563.

The spelling of 7861393549 in words is "seven billion, eight hundred sixty-one million, three hundred ninety-three thousand, five hundred forty-nine".