78206399 has 2 divisors, whose sum is σ = 78206400. Its totient is φ = 78206398.

The previous prime is 78206383. The next prime is 78206423. The reversal of 78206399 is 99360287.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 78206399 - 2⁴ = 78206383 is a prime.

It is a super-2 number, since 2×78206399² = 12232481689094402, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (78206309) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39103199 + 39103200.

It is an arithmetic number, because the mean of its divisors is an integer number (39103200).

Almost surely, 2^78206399 is an apocalyptic number.

78206399 is a deficient number, since it is larger than the sum of its proper divisors (1).

78206399 is an equidigital number, since it uses as much as digits as its factorization.

78206399 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 163296, while the sum is 44.

The square root of 78206399 is about 8843.4381888494. The cubic root of 78206399 is about 427.6424048227.

The spelling of 78206399 in words is "seventy-eight million, two hundred six thousand, three hundred ninety-nine".