401878686397 has 2 divisors, whose sum is σ = 401878686398. Its totient is φ = 401878686396.

The previous prime is 401878686379. The next prime is 401878686413. The reversal of 401878686397 is 793686878104.

It is a happy number.

Together with previous prime (401878686379) it forms an Ormiston pair, because they use the same digits, order apart.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 328765771161 + 73112915236 = 573381^2 + 270394^2 .

It is a cyclic number.

It is not a de Polignac number, because 401878686397 - 2¹⁵ = 401878653629 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (401878686317) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 200939343198 + 200939343199.

It is an arithmetic number, because the mean of its divisors is an integer number (200939343199).

Almost surely, 2^401878686397 is an apocalyptic number.

It is an amenable number.

401878686397 is a deficient number, since it is larger than the sum of its proper divisors (1).

401878686397 is an equidigital number, since it uses as much as digits as its factorization.

401878686397 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 97542144, while the sum is 67.

The spelling of 401878686397 in words is "four hundred one billion, eight hundred seventy-eight million, six hundred eighty-six thousand, three hundred ninety-seven".