78090101 has 2 divisors, whose sum is σ = 78090102. Its totient is φ = 78090100.

The previous prime is 78090079. The next prime is 78090109. The reversal of 78090101 is 10109087.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 49210225 + 28879876 = 7015^2 + 5374^2 .

It is an emirp because it is prime and its reverse (10109087) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-78090101 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (78090109) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39045050 + 39045051.

It is an arithmetic number, because the mean of its divisors is an integer number (39045051).

Almost surely, 2^78090101 is an apocalyptic number.

It is an amenable number.

78090101 is a deficient number, since it is larger than the sum of its proper divisors (1).

78090101 is an equidigital number, since it uses as much as digits as its factorization.

78090101 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 504, while the sum is 26.

The square root of 78090101 is about 8836.8603587473. The cubic root of 78090101 is about 427.4303223079.

Adding to 78090101 its reverse (10109087), we get a palindrome (88199188).

The spelling of 78090101 in words is "seventy-eight million, ninety thousand, one hundred one".