78837408389 has 2 divisors, whose sum is σ = 78837408390. Its totient is φ = 78837408388.

The previous prime is 78837408373. The next prime is 78837408401. The reversal of 78837408389 is 98380473887.

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., 52709272225 + 26128136164 = 229585^2 + 161642^2 .

It is a cyclic number.

It is not a de Polignac number, because 78837408389 - 2⁴ = 78837408373 is a prime.

It is a super-2 number, since 2×78837408389² (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 (78837408359) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39418704194 + 39418704195.

It is an arithmetic number, because the mean of its divisors is an integer number (39418704195).

Almost surely, 2^78837408389 is an apocalyptic number.

It is an amenable number.

78837408389 is a deficient number, since it is larger than the sum of its proper divisors (1).

78837408389 is an equidigital number, since it uses as much as digits as its factorization.

78837408389 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 65028096, while the sum is 65.

The spelling of 78837408389 in words is "seventy-eight billion, eight hundred thirty-seven million, four hundred eight thousand, three hundred eighty-nine".