78214538083421 has 2 divisors, whose sum is σ = 78214538083422. Its totient is φ = 78214538083420.

The previous prime is 78214538083403. The next prime is 78214538083427. The reversal of 78214538083421 is 12438083541287.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 71308127803396 + 6906410280025 = 8444414^2 + 2628005^2 .

It is an emirp because it is prime and its reverse (12438083541287) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-78214538083421 is a prime.

It is a super-2 number, since 2×78214538083421² (a number of 29 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (78214538083427) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39107269041710 + 39107269041711.

It is an arithmetic number, because the mean of its divisors is an integer number (39107269041711).

Almost surely, 2^{78214538083421} is an apocalyptic number.

It is an amenable number.

78214538083421 is a deficient number, since it is larger than the sum of its proper divisors (1).

78214538083421 is an equidigital number, since it uses as much as digits as its factorization.

78214538083421 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 10321920, while the sum is 56.

The spelling of 78214538083421 in words is "seventy-eight trillion, two hundred fourteen billion, five hundred thirty-eight million, eighty-three thousand, four hundred twenty-one".