78343087351421 has 2 divisors, whose sum is σ = 78343087351422. Its totient is φ = 78343087351420.

The previous prime is 78343087351367. The next prime is 78343087351481. The reversal of 78343087351421 is 12415378034387.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 77541321120025 + 801766231396 = 8805755^2 + 895414^2 .

It is a cyclic number.

It is not a de Polignac number, because 78343087351421 - 2¹⁸ = 78343087089277 is a prime.

It is a super-2 number, since 2×78343087351421² (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 (78343087351481) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39171543675710 + 39171543675711.

It is an arithmetic number, because the mean of its divisors is an integer number (39171543675711).

Almost surely, 2^{78343087351421} is an apocalyptic number.

It is an amenable number.

78343087351421 is a deficient number, since it is larger than the sum of its proper divisors (1).

78343087351421 is an equidigital number, since it uses as much as digits as its factorization.

78343087351421 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 13547520, while the sum is 56.

The spelling of 78343087351421 in words is "seventy-eight trillion, three hundred forty-three billion, eighty-seven million, three hundred fifty-one thousand, four hundred twenty-one".