78202913 has 2 divisors, whose sum is σ = 78202914. Its totient is φ = 78202912.

The previous prime is 78202909. The next prime is 78202933. The reversal of 78202913 is 31920287.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 76177984 + 2024929 = 8728^2 + 1423^2 .

It is a cyclic number.

It is not a de Polignac number, because 78202913 - 2² = 78202909 is a prime.

It is a super-2 number, since 2×78202913² = 12231391203371138, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 78202913.

It is not a weakly prime, because it can be changed into another prime (78202933) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39101456 + 39101457.

It is an arithmetic number, because the mean of its divisors is an integer number (39101457).

Almost surely, 2^78202913 is an apocalyptic number.

It is an amenable number.

78202913 is a deficient number, since it is larger than the sum of its proper divisors (1).

78202913 is an equidigital number, since it uses as much as digits as its factorization.

78202913 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 6048, while the sum is 32.

The square root of 78202913 is about 8843.2410913646. The cubic root of 78202913 is about 427.6360507664.

The spelling of 78202913 in words is "seventy-eight million, two hundred two thousand, nine hundred thirteen".