401655869 has 2 divisors, whose sum is σ = 401655870. Its totient is φ = 401655868.

The previous prime is 401655857. The next prime is 401655883. The reversal of 401655869 is 968556104.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 275991769 + 125664100 = 16613^2 + 11210^2 .

It is a cyclic number.

It is not a de Polignac number, because 401655869 - 2⁴ = 401655853 is a prime.

It is a super-2 number, since 2×401655869² = 322654874204290322, which contains 22 as substring.

It is a Sophie Germain prime.

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 (401655899) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 200827934 + 200827935.

It is an arithmetic number, because the mean of its divisors is an integer number (200827935).

Almost surely, 2^401655869 is an apocalyptic number.

It is an amenable number.

401655869 is a deficient number, since it is larger than the sum of its proper divisors (1).

401655869 is an equidigital number, since it uses as much as digits as its factorization.

401655869 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 259200, while the sum is 44.

The square root of 401655869 is about 20041.3539712266. The cubic root of 401655869 is about 737.8216122527.

The spelling of 401655869 in words is "four hundred one million, six hundred fifty-five thousand, eight hundred sixty-nine".