678399953501 has 2 divisors, whose sum is σ = 678399953502. Its totient is φ = 678399953500.

The previous prime is 678399953383. The next prime is 678399953503. The reversal of 678399953501 is 105359993876.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 341798083225 + 336601870276 = 584635^2 + 580174^2 .

It is a cyclic number.

It is not a de Polignac number, because 678399953501 - 2¹⁸ = 678399691357 is a prime.

It is a Sophie Germain prime.

Together with 678399953503, it forms a pair of twin primes.

It is a Chen prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (678399953503) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 339199976750 + 339199976751.

It is an arithmetic number, because the mean of its divisors is an integer number (339199976751).

Almost surely, 2^678399953501 is an apocalyptic number.

It is an amenable number.

678399953501 is a deficient number, since it is larger than the sum of its proper divisors (1).

678399953501 is an equidigital number, since it uses as much as digits as its factorization.

678399953501 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 55112400, while the sum is 65.

The spelling of 678399953501 in words is "six hundred seventy-eight billion, three hundred ninety-nine million, nine hundred fifty-three thousand, five hundred one".