78253511591 has 2 divisors, whose sum is σ = 78253511592. Its totient is φ = 78253511590.

The previous prime is 78253511459. The next prime is 78253511599. The reversal of 78253511591 is 19511535287.

It is a strong prime.

It is an emirp because it is prime and its reverse (19511535287) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 78253511591 - 2¹⁰ = 78253510567 is a prime.

It is a super-2 number, since 2×78253511591² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (78253511599) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39126755795 + 39126755796.

It is an arithmetic number, because the mean of its divisors is an integer number (39126755796).

Almost surely, 2^78253511591 is an apocalyptic number.

78253511591 is a deficient number, since it is larger than the sum of its proper divisors (1).

78253511591 is an equidigital number, since it uses as much as digits as its factorization.

78253511591 is an evil number, because the sum of its binary digits is even.

The product of its digits is 378000, while the sum is 47.

The spelling of 78253511591 in words is "seventy-eight billion, two hundred fifty-three million, five hundred eleven thousand, five hundred ninety-one".