78242511371501 has 2 divisors, whose sum is σ = 78242511371502. Its totient is φ = 78242511371500.

The previous prime is 78242511371489. The next prime is 78242511371503. The reversal of 78242511371501 is 10517311524287.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 77066802712900 + 1175708658601 = 8778770^2 + 1084301^2 .

It is a cyclic number.

It is not a de Polignac number, because 78242511371501 - 2¹⁴ = 78242511355117 is a prime.

It is a super-2 number, since 2×78242511371501² (a number of 29 digits) contains 22 as substring.

It is a Sophie Germain prime.

Together with 78242511371503, it forms a pair of twin primes.

It is a Chen prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (78242511371503) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39121255685750 + 39121255685751.

It is an arithmetic number, because the mean of its divisors is an integer number (39121255685751).

Almost surely, 2^{78242511371501} is an apocalyptic number.

It is an amenable number.

78242511371501 is a deficient number, since it is larger than the sum of its proper divisors (1).

78242511371501 is an equidigital number, since it uses as much as digits as its factorization.

78242511371501 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 470400, while the sum is 47.

Adding to 78242511371501 its reverse (10517311524287), we get a palindrome (88759822895788).

The spelling of 78242511371501 in words is "seventy-eight trillion, two hundred forty-two billion, five hundred eleven million, three hundred seventy-one thousand, five hundred one".